Mastering Python Programming: A Complete Guide for Beginners

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# Your first Python program
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print("Hello, World!")
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print("Welcome to Python programming!")
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# This is a comment - Python ignores it
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# Comments help explain your code
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name = "Student"
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print(f"Hello, {name}! Ready to learn Python?")

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# Indentation is crucial in Python
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if True:
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    print("This is indented")  # 4 spaces or 1 tab
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    print("Same level")
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# Variables don't need type declaration
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age = 25
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name = "Alice"
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is_student = True
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# Multiple assignment
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x, y, z = 1, 2, 3
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# Print with formatting
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print(f"{name} is {age} years old")

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# Numbers
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integer_num = 42
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float_num = 3.14
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# Strings
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text = "Hello Python"
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multiline = """This is a
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multi-line string"""
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# Boolean
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is_valid = True
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# Lists (mutable, ordered)
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fruits = ["apple", "banana", "orange"]
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fruits.append("grape")
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# Tuples (immutable, ordered)
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coordinates = (10, 20)
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# Dictionaries (key-value pairs)
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student = {
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    "name": "John",
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    "age": 20,
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    "grade": "A"
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}
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# Sets (unique, unordered)
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unique_numbers = {1, 2, 3, 4, 5}

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# If-elif-else
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score = 85
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if score >= 90:
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    grade = "A"
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elif score >= 80:
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    grade = "B"
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elif score >= 70:
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    grade = "C"
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else:
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    grade = "F"
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print(f"Your grade is: {grade}")
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# For loop
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fruits = ["apple", "banana", "cherry"]
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for fruit in fruits:
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    print(f"I like {fruit}")
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# While loop
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count = 0
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while count < 5:
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    print(f"Count: {count}")
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    count += 1
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# List comprehension (Pythonic way)
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squares = [x**2 for x in range(10)]
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even_numbers = [x for x in range(20) if x % 2 == 0]

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# Simple function
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def greet(name):
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    return f"Hello, {name}!"
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# Function with default parameters
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def greet_with_time(name, time="morning"):
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    return f"Good {time}, {name}!"
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# Function with multiple return values
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def get_user_info():
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    name = "Alice"
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    age = 25
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    city = "New York"
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    return name, age, city
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# Using the functions
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message = greet("Python Learner")
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print(message)
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morning_msg = greet_with_time("Bob")
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evening_msg = greet_with_time("Charlie", "evening")
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user_name, user_age, user_city = get_user_info()
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print(f"{user_name} is {user_age} years old from {user_city}")
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# Lambda functions (anonymous functions)
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square = lambda x: x**2
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print(square(5))  # Output: 25
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# Map, filter, reduce
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numbers = [1, 2, 3, 4, 5]
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squared = list(map(lambda x: x**2, numbers))
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evens = list(filter(lambda x: x % 2 == 0, numbers))