# Python Cheat Sheet

## Table of Contents

1. [Variables](#variables)
2. [Data Types](#data-types)
3. [Operators](#operators)
4. [Control Structures](#control-structures)
5. [Functions](#functions)
6. [Lists](#lists)
7. [Strings](#strings)
8. [Dictionaries](#dictionaries)
9. [Tuples](#tuples)
10. [Sets](#sets)
11. [File Handling](#file-handling)
12. [Exception Handling](#exception-handling)
13. [Classes and Objects](#classes-and-objects)

## Variables

### Declaration and Assignment
```python
variable_name = value
```

### Variable Types
- String: `string_variable = "Hello"`
- Integer: `int_variable = 42`
- Float: `float_variable = 3.14`
- Boolean: `bool_variable = True`

## Data Types

### Basic Types
- String
- Integer
- Float
- Boolean

### Compound Types
- List
- Tuple
- Set
- Dictionary

## Operators

### Arithmetic Operators
```python
+, -, *, /, %, ** (exponentiation), //
```

### Comparison Operators
```python
==, !=, <, >, <=, >=
```

### Logical Operators
```python
and, or, not
```

### Assignment Operators
```python
=, +=, -=, *=, /=, %=
```

## Control Structures

### If Statement
```python
if condition:
    # code to be executed if the condition is true
elif another_condition:
    # code to be executed if the previous condition was false and this one is true
else:
    # code to be executed if all conditions are false
```

### For Loop
```python
for i in range(5):
    # code to be executed in each iteration
```

### While Loop
```python
while condition:
    # code to be executed as long as the condition is true
```

## Functions

### Function Declaration
```python
def function_name(param1, param2):
    # code to be executed
    return result  # optional
```

### Function Call
```python
result = function_name(arg1, arg2)
```

## Lists

### List Declaration
```python
my_list = [1, 2, 3, "hello", True]
```

### List Operations
```python
my_list.append(4)  # Add an element to the end
my_list.remove("hello")  # Remove a specific element
```

## Strings

### String Concatenation
```python
string1 = "Hello"
string2 = "World"
concatenated = string1 + " " + string2
```

### String Methods
```python
len(my_string)  # Length of the string
my_string.find("find")  # Index of the first occurrence of "find"
my_string.split(",")  # Split the string into a list
```

## Dictionaries

### Dictionary Declaration
```python
my_dict = {"key1": "value1", "key2": "value2"}
```

### Dictionary Operations
```python
my_dict["new_key"] = "new_value"  # Add a new key-value pair
del my_dict["key1"]  # Remove a key-value pair
```

## Tuples

### Tuple Declaration
```python
my_tuple = (1, 2, 3, "hello", True)
```

### Immutable Nature
```python
# Tuple elements cannot be changed once set
my_tuple[0] = 4  # This will result in an error
```

## Sets

### Set Declaration
```python
my_set = {1, 2, 3, 3, 4}
```

### Set Operations
```python
my_set.add(5)  # Add an element to the set
my_set.remove(3)  # Remove an element from the set
```

## File Handling

### Reading from a File
```python
with open("filename.txt", "r") as file:
    file_content = file.read()
```

### Writing to a File
```python
with open("filename.txt", "w") as file:
    file.write("Hello, World!")
```

## Exception Handling

### Try-Except Block
```python
try:
    # code that may raise an exception
except Exception as e:
    # handle the exception
    print("Error:", e)
```

## Classes and Objects

### Class Declaration
```python
class MyClass:
    def __init__(self, name):
        self.name = name

    def say_hello(self):
        print(f"Hello, {self.name}!")
```

### Object Instantiation
```python
obj = MyClass("John")
obj.say_hello()  # Outputs: Hello, John!
```

```