variable = 1
Variable = 2 # Different from 'variable'
Installation & Setup
Download from python.org
Verify installation:
bash
python --version
# or
python3 --version
Running Python
Scripts: python filename.py
Interactive: python or python3 in terminal
IDEs: VS Code, PyCharm (best for large projects)
Notebooks: Jupyter (best for data analysis)
Brief History
Created by Guido van Rossum in 1991. Named after Monty Python. Emphasizes code readability.
Variables
python
# Basic assignment
name = "Alice" # str
age = 25 # int
price = 9.99 # float
is_active = True # bool
# Multiple assignment
x, y, z = 1, 2, 3
Functions
Basic Function
python
def greet():
print("Hello!")
With Parameters
python
def greet(name):
print(f"Hello, {name}!")
With Return Value
python
def add(a, b):
return a + b
Default Parameters
python
def greet(name="Guest"):
print(f"Hello, {name}!")
Data Types
Numeric
python
int_num = 10 # Integer
float_num = 10.5 # Floating point
complex_num = 1j # Complex
Sequence Types
python
list_ex = [1, "two", 3.0] # Mutable
tuple_ex = (1, "two", 3.0) # Immutable
range_ex = range(5) # range(0, 5)
Text Type
python
string = "Hello World"
Boolean
python
true_val = True
false_val = False
Set Types
python
set_ex = {1, 2, 3} # Unordered, unique
frozen_set = frozenset({1, 2, 3}) # Immutable set
Dictionary
python
dict_ex = {"name": "Alice", "age": 25}
Type Conversion
python
int("10") # String to integer
str(10) # Integer to string
float("10.5") # String to float
list((1,2,3)) # Tuple to list
