#Code2Create: Python Basics

1
Before we start learning let’s
Download
“Python” & “Pycharm”

2
Environment
Website: python.org/downloads/

3
For Mac OS
Environment
1. From Downloads file choose python-3.9.2 file
2. Click continue
3. Click agree.
4. Insert your password then click install.

5
Downloading PyCharm
code editor
The Python IDE Integrated development environment
Website:
https://www.jetbrains.com/pycharm/do
wnload/#section=mac

6
Download PyCharm (Cont.)
1. Click on “Download” 2. Choose “Community” edition click “Download.

7
Mac users
3. Go to downloads and click on
PyCharm folder.
4. Drag PyCharm icon to
Applications folder.
5. This window will appear because it is
downloaded from the internet.

8
Windows users
3. Click on the downloaded PyCharm folder then click “next”.
4. Click “next”.
5. Check the 64-bit launcher then press ”next”.
6. Click ”install”

9
Windows users
7. Click on “finish”.
8. Click “Accept”.
9. Check ”OK”.
10. Click ”Don’t send”

10
• Choose the first choice then click next , next, next and next again.
• Finally, this is the main page of PyCharm. Click on create new
project.

11
What are we going to learn in part 1?
• Basic programming terminologies.
• Writing comments.
• Variables, String Numbers.
• Data types: Integer, Float, String, Boolean.
• print function.
• Input function.
• Python conditional statements (If/elif/else statements) & Operators.
• Loops (for, Nested loop, while).

12
Basic Programming terms
• What is programming?
• Programming is using a code or source code, which is a sequence of
instructions to develop a program that will provide an output solution using
several tools such as a programming language & programming language
editor.
• output: The messages printed to the user by a program.
• console: The text box onto which output is printed.

13
Basic Programming terms (cont.)
• What is programming language?
• Programming language is a tool used to create a program by writing human
like language in a specific structure (syntax) using an editor that will translate
the human language to binary language of zeros and ones, which is the
computer language.
• syntax: The set of legal structures and commands that can be used in a particular
programming language.
• Types of programming languages:
• Open Source programming language:
• Python
• Paid Source

14
What is ?
• Python is an open source and cross-platform programming language
that has a general purpose used widely by developer's community to
create websites, games, machine learning modules and more.
• Why should you learn Python?
● Big Community
● General-purpose
● Open-source and cross-platform
● High productivity
● Memory safe

15
What is Python?
• High-level programming language.
• Invented in the Netherlands, early 90s by Guido van Rossum
• Named after Monty Python
• Open sourced from the beginning
• Increasingly popular

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Why Python?
• Simple
• Python is a simple and minimalistic language in nature
• Reading a good python program should be like reading English
• Easy to Learn
• Cool documentation
• Free & Open source
• Freely distributed and Open source
• Maintained by the Python community
• High Level Language
• Portable
• The same code can run on Windows, Linux, MAC machines

Let’s Start programming with
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Comments (Best Practice)
• Comments: notes of explanation within a program
• Ignored by Python interpreter
• Intended for a person reading the program’s code
• Begin with a # character
• Types of comments:
• Single Line Comments [ using # ]
• Multi-Line Comments """ type whatever here... """
• Example:
• Output:
# This line is a comment.
print("This line is not a comment, it is
code.")
This line is not a comment, it is code.

19
Variables
• Rules for naming variables in Python:
• Variable name cannot be a Python keyword
• Variable name cannot contain spaces
• First character must be a letter or an underscore
• After first character may use letters, digits, or underscores
• Variable names are case sensitive
• Variable name should reflect its use
• Variable: name that represents a
value stored in the computer
memory
• Used to access and manipulate
data stored in memory
• A variable references the value it
represents
• Assignment statement: used to
create a variable and make it
reference data
• Defining a variable:
• variable = expression
• Example:
age = 29
student_name= ’Maryam’

20
Variable Name Rules
1. Names cannot start with a number.
ex: 2made x
2. Names cannot contain spaces, use _ instead.
ex: two days x, and make it “two_days”
3. Names cannot start with symbols :’
",<>/?|()!@#$%^&*~-+ 4.
It's best practice to use names with lowercase.

21
Types of expressions that can be assigned
to a variable
 Float
 x = 3.56
 String (str)
 L = “Hello”
 Integer (int)
 Score_2 = 234
Boolean
 Pass_test = True OR False

22
print function
• Print function is used to give us the output of a variable stored value , or
print an input from the end-user or the developer of the program.
• For example:
• Variable stored value as output syntax:
x=3
y=5
result= x+y
print(result)
• Input from the developer syntax:
print(“Hello World”)
• Input from the end-user syntax:
name= input(‘What is your name? ‘)
print(‘Hi ‘+name)

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print
• Print function used to display and print a line of output on the console
• Example:
print("Hello, world!")
print()
print("This program produces")
print("four lines of output")
• Its output:
Hello, world!
This program produces
four lines of output

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Strings
• Strings (str)
• Must be enclosed in single (‘) or double (“) quote marks
• For example:
my_string = "This is a double-quoted string."
my_string = 'This is a single-quoted string.’
my_string= ‘ This is a “single-quoted” string.’
my_string= “ This is a ‘double-quoted’ string.”
double quotes to wrap single quotes
single quotes to wrap double quotes

25
Strings
• Example:
• Output:
message = "Hello Python World! "
print(message)
message = "Python is my favorite language! "
print(message)
Hello Python World!
Python is my favorite language!

26
String Concatenation
• String Concatenation: The + operator is used to concatenate strings
s = ‘Love’ + ‘Coding’
print(s) // LoveCoding
letter = ‘z-’
print(letter * 10) // z-z-z-z-z-z-z-z-z-z-

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Built In string methods
1. Upper: Returns a copy of the string converted to uppercase
2. Lower: Returns a copy of the string converted to lowercase
3. Capitalize: Returns a copy of the string with only it’s first letter
capitalized
4. Split: It splits a string, and also allows you to split on any element of
the string

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Strings
• String Functions
• len(string) - number of characters in a string
• str.lower(string) - lowercase version of a string
• str.upper(string) - uppercase version of a string
• str.isalpha(string) - True if the string has only alpha chars
• Many others: split, replace, find, format, etc.
• Note the “dot” notation: These are static methods.

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Strings
• Example:
• Output:
s1= "Welcome to 500 course"
print(len(s1))
print(str.lower(s1))
print(str.upper(s1))
print(str.isalpha(s1))
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welcome to 500 course
WELCOME TO 500 COURSE
False

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Strings
• escape sequence: A sequence of characters used to represent certain
special characters in a string.
t tab character
n new line character
" quotation mark character
backslash character

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Strings
• Example:
• Output:
print("Hello everyone! ")
print("t Hello everyone! ")
print("Hello t everyone! ")
print("Hello n everyone! ")
Hello everyone!
Hello everyone!
Hello everyone!
Hello
everyone!

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Numbers
• Numbers in Python can be in a form of:
• Integer (int) , for example:
age = 37
• Float, for example:
gpa = 3.67
• You can do all of the basic operations
with numbers.
• + for addition
• - for subtraction
• * for multiplication
• / for division
• ** for exponent
• () for parenthesis
print(3+4)
print(1.6-9.5)
print(2**2)
print(5.5/2)
result= 2+ 3*4
print(result)
result= (2+ 3)*4
print(result)
7
-7.9
4
2.75
14
20

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Numbers
• A simple way to view the effect of an assignment is to assume that when
a variable changes, its old value is replaced
• You can change the value of a variable at any point.
x = 2
print(x)
x = 2.3
print(x)
2
Before
2.3
After
x x

34
Variables, Strings, and Numbers
• Dealing with simple numerical data is fairly straightforward in Python.
• There are different types of numbers: Integer and Float are most used.
• Integer like 3 , Float like 4.8
• You can do all of the basic operations with numbers.
• + for addition
• - for subtraction
• * for multiplication
• / for division
• ** for exponent
• () for parenthesis
• Higher precedence performed first
• Same precedence operators execute from left to right

35
Numbers
• Example:
• Calculate the following formula:
𝑎2
+ 𝑏3
× 𝑐
where a= 5, b=4, c=8
save the values in variables.

36
Assigning input
• So far, we have been using values specified by programmers and printed
or assigned to variables
• How can we let users (not programmers) input values?
• In Python, input is accomplished via an assignment statement combined
with a built-in function called input
• When Python encounters a call to input, it prints <prompt> (which is a
string literal) then pauses and waits for the user to type some text and
press the <Enter> key

37
Assigning input
• Here is a sample interaction with the Python interpreter:
• Example:
• Output:
• Notice that whatever the user types is then stored as a string
• What happens if the user inputs a number?
name= input("Enter your name ")
Enter your name Fatma

38
Assigning input
• In Python, the + operator can only concatenate strings as Python is
a strongly typed programming language.
• Example:
• Output:
Enter your favorite course name python
your favorite course name is python
name= input("Enter your favorite course name ")
print("your favorite course name is "+ name)

39
Assigning input
• we can convert the string output of the input function into an integer or
a float using the built-in int and float functions
• Example:
• Output
number= int(input("Enter a number "))
Enter a number 3 An integer

40
Assigning input
• We can convert the string output of the input function into an integer or
a float using the built-in int and float functions
• Example:
• Output
number= float(input("Enter a number "))
Enter a number 3.7 A float

41
Assigning input
• We can do various kinds of conversions between strings, integers and
floats using the built-in int, float, and str functions
integer  float
integer  string
string  float
string  integer
float  integer
float  string
x= 10
print(x)
print(float(x))
print(str(x))
y='20'
print(y)
print(float(y))
print(int (y))
z= 30.0
print(z)
print (int(z))
print (str(z))
30.0
30
30.0
20
20.0
20
10
10.0
10

42
If statement
Making Decisions – Controlling Program Flow
• To make interesting programs, you must be able to make decisions about data
and take different actions based upon those decisions.
• if statement: Executes a group of statements only if a certain condition is
true. Otherwise, the statements are skipped.
• Syntax of the If statement:
if condition:
Statement
Statement
• First line known as the if clause
• Includes the keyword “if” followed by “condition”
• The condition can be true or false
• When the if statement executes, the condition is tested, and if it is true the block statements are
executed. otherwise, block statements are skipped.

43
If statement
• Example:
• Output:
• The indented block of code following an if statement is executed if
the Boolean expression is true, otherwise it is skipped.
gpa = 3.4
if gpa > 2.0:
print ("Your application is accepted.”)
Your application is accepted.

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if/else statements
• if/else statement: Executes one block of statements if a certain
condition is True, and a second block of statements if it is False.
• Example:
gpa = 1.4
if gpa > 2.0:
print("Welcome to University!")
else:
print("Your application is denied.")
print(“Good luck”)

45
If/ELIF/ELSE
• If you have several mutually exclusive choices, and want to guarantee that only
one of them is executed, you can use an IF/ELIF/ELSE statements. The ELIF
statement adds another boolean expression test and another block of code that
is executed if the boolean expression is true.
• Syntax:
if boolean expression :
STATEMENT
STATEMENT
elif 2nd boolean expression :
STATEMENT
STATEMENT
else:
STATEMENT
STATEMENT

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If/ELIF/ELSE- Example
numberOfWheels = 3
if ( numberOfWheels == 1):
print “You are a Unicycle!”
elif (numberOfWheels == 2):
print “You are a Motorcycle!”
print “You are a Tricycle!”
print “You are a Car!”
else:
print “That's a LOT of wheels!”
• Only the print statement from the first true boolean expression is
executed.

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Loops
• A loop statement allows us to execute a
statement or group of statements
multiple times.
• Two types of loops:
• for loop:
Executes a sequence of statements multiple
times and abbreviates the code that manages
the loop variable.
• while loop:
Repeats a statement or group of statements
while a given condition is TRUE. It tests the
condition before executing the loop body.

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for Loop
• for loop: Repeats a set of statements over a group of values.
• Syntax:
• Example:
for < var > in range<sequence or group of valuse>:
<statements>
for i in range(5):
... print(i)
0
1
2
3
4
• Rules of loops:
• We indent the statements to be
repeated with tabs or spaces.
• VariableName gives a name to each
value, so you can refer to it in the
statements.
• GroupOfValues can be a range of
integers, specified with the range
function.

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for
• Example:
• Output:
• Example:
• Output:
for x in (1 , 5):
print(x," Hello")
1 Hello
5 Hello
for x in range(1 , 5):
print(x," Hello")
1 Hello
2 Hello
3 Hello
4 Hello

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for
• Example:
• Output:
n = 100
sum = 0
for counter in range(1,n+1):
sum = sum + counter
print("Sum of 1 until 100:”, sum)
Sum of 1 until 100: 5050

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Nested Loop
• Loops defined within another loop is called Nested loop. When an outer loop contains an inner loop
in its body it is called Nested looping.
• Syntax:
for <expression>:
for <expression>:
body
• for example:
Stops summing at 4
because it is grater than
5 and does not count 5
as an output
2+1 =3
3+1=4
4+1=5 it will give
output 4 and
ends the output
result as 4
for a in range (1,5):
for b in range (1,a+1):
print(a)

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while
• while loop: Executes a group of statements as long as a condition is
True.
• good for indefinite loops (repeat an unknown number of times)
• Syntax:
while condition:
statements
• Example: Output:
number = 1
while number < 200:
print (number)
number = number * 2
1
2
4
8
16
32
64
128

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Let’s review
what we’ve learned
so far!

54
Review
1. Which of the following are legal python identifiers (circle your answers).
a) hello
b) 5times
c) int
d) Pepper2
e) iden_tifier
f) APPLES
g) if
h) _1xyz

55
Review
1. Which of the following are legal python identifiers (circle your answers).
a) hello
b) 5times
c) int
d) Pepper2
e) iden_tifier
f) APPLES
g) if
h) _1xyz

56
Review
2. Which of the following mark the beginning of a comment?
a) //
b) /*
c) /**
d) #
3. Select all option(s) that print Python-is-very-easy
a) print(“Python‟, “is‟, “very‟, “easy”)
b) b) print(“Python‟, “is‟, “very‟, “easy‟ + “-‟ * 4 c)
c) print(“Python-‟ + “is - very - easy‟)
d) d) print(“Python‟ + “-‟ + “is‟ + “-‟ + “very‟ + “-‟ + “easy‟)

57
Review
2. Which of the following mark the beginning of a comment?
a) //
b) /*
c) /**
d) #
3. Select all option(s) that print Python-is-very-easy
a) print(“Python‟, “is‟, “very‟, “easy”)
b) print(“Python‟, “is‟, “very‟, “easy‟ + “-‟ * 4 c)
c) print(“Python-‟ + “is - very - easy‟)
d) print(“Python‟ + “-‟ + “is‟ + “-‟ + “very‟ + “-‟ + “easy‟)

58
Review
4. What gets printed when Python execute that program
x ='5’
y = 2
z = x+y
Print(z)
a) 52
b) 7
c) Syntax Error
d) z

59
Review
4. What gets printed when Python execute that program
x ='5’
y = 2
z = x+y
Print(z)
a) 52
b) 7
c) Syntax Error
d) z

60
Review
7. Write a Python program that can take four float numbers from the
console/ user and displays their average.

61
Review
7. Write a Python program that reads four float numbers from the
console and displays their average.
x= float(input (" Enter first number"))
y= float(input (" Enter second number"))
z= float(input (" Enter third number"))
w= float(input (" Enter fourth number"))
av= (x+y+z+w)/4
print("The aveage is ", av)

62
Exercise
Write a Python program that reads two numbers and determines the following:
If two numbers are equal, then it will print first number = second number
If the first number is greater than the second number, it will print first number > second number
If the first number is less than the second number, it will print first number < second number
Sample output 1:
Enter the first number:
3
Enter the second number:
5
3 < 5
Sample output 2:
Enter the first number:
7
Enter the second number:
7
7 = 7

63
Exercise Solution
x=int(input("Enter the first number: "))
y=int(input("Enter the second number: "))
if (x==y):
print (x," = ", y)
elif (x<y):
print(x," < ", y)
else:
print(x," > ", y)

Contact info
• Maryam AlMahdi
• E-mail: mariam.almahdi@outlook.com
• Instagram: @gdgkwt_maryam
64

65
Now let’s continue
Python basics part 2
with Eng. Mahdi AlFaraj

What are we going to learn?
• Functions
• Global and local variables
• Python Lists, Tuples, Sets, Dictionaries
• Python Arrays
• Python Try… Except
• Object-oriented programming
• Python Classes/Objects
• Modules and modules’ methods
66

Functions
• A function is a block of code which only runs when it is called.
• You can pass data, known as parameters, into a function.
• A function can return data as a result.
Creating a function syntax:
Calling a function:
• To call a function, use the function name followed by parenthesis:
67

Functions
Function Arguments:
• Information can be passed into functions as arguments.
• Arguments are specified after the function name, inside the
parentheses. You can add as many arguments as you want, just
separate them with a comma.
Example:
def my_function(fname):
print(fname + " Johnson")
my_function("Emil")
my_function("Tobias")
my_function("Linus") 68

Functions
Return Values:
• To let a function return a value, use the return statement:
69

Functions
Example:
def bar(x) :
return x * x
print(bar(3))
Output:
9
• Note that the function bar takes
one parameter and returns the
square of the x value inputted.
70

Global and local variables
• A global variable is a variable declared outside of a function
• Scope: this variable can be used in the entire program
• A local variable is a variable declared inside of a function.
• Scope: this variable is used only in the function it is declared in.
71

• Will this code work?
Yes it will work!!
72

• We can use the global key word if we want to change a global variable
inside a function.
• Will this code work?
Yes it will work!!
73

Lists:
• Lists are used to store multiple items in a single variable.
• Lists are one of 4 built-in data types in Python used to store
collections of data, the other 3 are Tuple, Set, and Dictionary, all with
different qualities and usage.
• Lists are created using square brackets and each item is separated by
a comma.
• Examples of Lists:
my_list = [1,2,3]
my_list = [‘strings’, 1, 2, 3.9, True, [1,2,3] ]
print(len(my_list))
List can contain
numbers, strings,
nested lists, etc.
The len() function will tell you how many
items are in the sequence of your list
Python Lists, Tuples, Sets, Dictionaries
74

• A list or array is a sequence of items where the entire sequence is
referred to by a single name (i.e. s) and individual items can be selected
by indexing (i.e. s[i]). The first item in the list has an index of 0.
• Python lists are dynamic. They can grow and shrink on demand.
• In other programming languages, arrays are generally a fixed size,
meaning that when you create the array, you have to specify how many
items it can hold.
• Python lists are heterogeneous, a single list can hold arbitrary data
types.
• Arrays are generally homogeneous, meaning they can hold only one data
type.
75

List Positive and Negative Indices:
t = [23, ‘abc’, 4.56, 3, ‘def’]
Positive index: count from the left, starting with 0
print(t[1])
‘abc’
Negative index: count from right, starting with –1
Print(t[-3])
4.56
76

List Operations:
77

• List Concatenation:
my_list = ['one’, 'two’]
my_list = my_list + ['new item’]
print(my_list) // [‘one’, ‘two’, ‘new item’]
• Replicating a list:
my_list = ['1', '2'] *2
print(my_list) // ['1', '2', '1', '2']
78

List Operations (Slicing)
Python List Slicing Syntax:
79

Examples:
t = [23, ‘abc’, 4.56, 3, ‘def’]
Returns copy of list with subset of original members. Start copying at first
index, and stop copying before the second index
print t[1:4]
[‘abc’, 4.56, 3]
You can also use negative indices
print t[1:-1]
[‘abc’, 4.56, 3]
80

Examples:
t = [23, ‘abc’, 4.56, 3, ‘def’]
Omit first index to make a copy starting from the beginning of list
print(t[:2])
[23, ‘abc’]
Omit second index to make a copy starting at 1st index and going to end of the
list
print(t[2:])
[4.56, 3, ‘def’]
81

List Operations (Copying the whole list)
• [ : ] makes a copy of an entire sequence
print(t[:])
[23, ‘abc’, 4.56, 3, ‘def’]
82

List Operations ( “in” Operator)
• Boolean test whether a value is inside a list:
t = [1, 2, 4, 5]
print(3 in t)
False
print(4 in t)
True
• For strings, tests for substrings
a = 'abcde’
print('c' in a)
True
'cd' in a
True
Print('ac' in a)
False
• Careful: the in keyword is also used in the syntax of for loops and list
comprehensions
83

• Example
Code:
• Output:
S1 = ['yellow', 'red', 'blue', 'green', 'black’]
S2=[1, 2, 3]
print (S1)
Print(S1+S2)
print (S1[0])
print (S2*3)
print (len(S1))
print (S1[0:2])
Print( 1 in S2)
['yellow', 'red', 'blue', 'green', 'black']
['yellow', 'red', 'blue', 'green', 'black’,1,2,3]
yellow
[1, 2, 3, 1, 2, 3, 1, 2, 3]
5
[‘yellow', ‘red’]
True
84

• Example
Code:
• Output:
S = ['yellow', 'red', 'blue', 'green', 'black']
print (S[-1])
S[2]='silver'
print(S[:])
black
['yellow', 'red', 'silver', 'green', 'black’]
85

List Functions:
86

List Functions:
• len(ex_list): number of elements in list (top level).
• min(ex_list): smallest element. Must all be the same type!
• max(ex_list): largest element, again all must be the same type
• sum(ex_list): sum of the elements, numeric only
87

• List Functions Examples:
• Output:
C = ['A', 'B', 'C', 'D']
print (C.index('C'))
2
C = ['C', 'B', 'A', 'D’]
print (len(C))
4
C = ['A', 'B', 'C', 'D’]
print (C.count(‘A’))
D = ['A', 'B', ‘A', ‘D’]
print (D.count(‘A’))
1
2
88

• Output:
[ 'B', 'C', 'D','A']
C = ['A', 'B', 'C', ‘D’, ‘A’]
C.remove('A’)
print (C)
C = ['C', 'B', 'A', 'D']
C.sort()
print (C)
['A', 'B', 'C', 'D']
C = ['A', 'B', 'C', 'D']
C.reverse()
print (C)
['D', 'C', 'B', 'A']
89

• Output:
C = ['A', 'B', 'C', 'D']
C.append ('X')
print (C)
['A', 'B', 'C', 'D', 'X’]
C = ['A', 'B', 'C', 'D']
V = ['Z','Y','Q']
C.extend (V)
print (C)
['A', 'B', 'C', 'D', 'Z', 'Y', 'Q']
C = ['A', 'B', 'C', 'D']
V = [‘X','Y',’Z']
C.insert (1,'K')
print (C)
C.insert (0,V)
print (C)
C.insert (0, [‘J',’I',’M’])
print (C)
['A', 'K', 'B', 'C', 'D’]
[[‘X', 'Y', ‘Z'], 'A', 'K', 'B', 'C', 'D’]
[[‘J', ‘I', ‘M'], ['Z', 'Y', 'Q'],'A','K', 'B', 'C', 'D']
90

• Output:
E = [1, 3, 5, 7, 9]
print (min(E))
1
E = [1, 3, 5, 7, 9]
print (max(E))
9 25
E = [1, 3, 5, 7, 9]
print (sum(E))
E = [1, 3, 1, 7, 9]
print (E.count(1))
print (E.count(8))
2
0
91

Tuples:
• A tuple is a collection which is ordered and unchangeable.
• Tuples are written with round brackets.
• Tuple items are indexed: the first item has index [0], the second item
has index [1] etc.
Example:
92

Sets:
• A set is a collection which is both unordered and unindexed.
• Unordered: Set items can appear in a different order every time you
use them, and cannot be referred to by index or key.
• Set items are unordered, unchangeable, and do not allow duplicate
values.
• Sets are written with curly brackets.
93

Sets:
Example (running same code twice):
Output 1: Output 2:
94

Dictionaries:
• Dictionaries are used to store data values in key:value pairs.
• A dictionary is a collection which is ordered (Python 3.7+), changeable
and does not allow duplicates.
• Dictionaries are written with curly brackets, and have keys and values:
95

• Python offers built-in data types for storing collection of data such as
Lists, Tuples, Sets etc.
• However, there is a module called array that allows us to use arrays to
store a collection of numeric values of same numeric data type.
• Lists are much more flexible than arrays. They can store elements of
different data types including strings. And, if you need to do
mathematical computation on arrays and matrices, you are much
better off using something like NumPy.
Python Arrays
96

• When an error occurs, or exception as we call it, Python will normally
stop and generate an error message.
• These exceptions can be handled using the try statement.
• The try block lets you test a block of code for errors.
• The except block lets you handle the error.
• Example (variable x is never defined):
Python Try… Except
97

• We can define as many exception blocks as we want.
• Example: if you want to execute a special block of code for a special
kind of error:
98

• Python common built-in Exceptions Hierarchy:
99

• Real use scenario:
try:
f = open("demofile.txt")
f.write("New user: Alex")
f.close()
except:
print("Something went wrong when writing to the file")
100

Object-Oriented Programming
• Object-oriented programming (OOP) is a method of structuring a program
by bundling related properties and behaviors into individual objects.
• For instance, an object could represent a person with properties like a
name, age, and address and behaviors such as walking, talking, breathing,
and running. Or it could represent an email with properties like a recipient
list, subject, and body and behaviors like adding attachments and sending.
• Put another way, object-oriented programming is an approach for
modeling concrete, real-world things, like cars, as well as relations between
things, like companies and employees, students and teachers, and so on.
OOP models real-world entities as software objects that have some data
associated with them and can perform certain functions. 101

Python Classes & Objects
• Python is an object-oriented programming language.
• Almost everything in Python is an object, with its properties and
methods.
• A Class is like an object constructor, or a "blueprint" for creating
objects
102

• To understand the meaning of classes we have to understand the
built-in __init__() function.
• All classes have a function called __init__(), which is always executed
when the class is being initiated.
• Use the __init__() function to assign values to object properties, or
other operations that are necessary to do when the object is being
created.
103

Example: Create a class named Person, use the __init__() function to
assign values for name and age:
104

• Objects can also contain methods. Methods in objects are functions
that belong to the object.
Example: Insert a function that prints a greeting, and execute it on the
p1 object.
105

• The self parameter is a reference to the current instance of the class,
and is used to access variables that belongs to the class.
• You can modify properties of objects like this:
• You can delete properties of an object, or the object itself entirely by
using the del keyword:
106

Exercise:
Create a class named "Car" with the following 3 attributes: brand, color, price. The class
should have a function for printing out the object's details. Create a new object and call
the function to print the values assigned.
Hint: Remember the format for creating a class:
class Car:
def __init__(self, brand, color, price):
self.brand = brand
…
…
Finished early? Add a line of code for modifying the color of the car object being added to
YELLOW.
107

Exercise Solution:
Modification for color
108

Exercise Solution Output:
Exercise Solution Output with Modification:
109

Modules & Modules’ methods
What is a module?
• Consider a module to be the same as a code library.
• A file containing a set of functions you want to include in your application.
• The highest-level structure of Python
• Each file with the .py suffix is a module
• Each module has its own namespace
• Example of syntax:
• import mymodule Brings all elements of mymodule in, but must refer to as
mymodule.
• Examples of common Modules:
Math Module Turtle Module Pandas Module
Random Module Matplotlib Module 110

Modules & Modules’ methods
Example for creating and using a module:
• To create a module just save the code you want in a file with the file
extension .py:
• We can now use the module we just created by using the import
statement:
111

Thank you!
GDG Kuwait would like to thank you for attending today’s
workshop and wishes you all the best in your learning
journey!
112

References
• https://www.w3schools.com/python/
• Python Cheat Sheet by Mosh Hamedani
• Ms. Fatimah Al-Rashed – Python lab
113

#Code2Create: Python Basics

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