Basic constructs in Python

basic_python.md

1. Variable Assignment:

my_variable = 42 # now my_variable references 42

2. Primitive Data Types:

my_integer = 42              # int
my_float = 3.14              # float
my_string = "Hello, World!"  # string
my_boolean = True            # boolean

3. How to Use Dictionaries:

my_dict = {"key1": "value1", "key2": "value2"}
print(my_dict["key1"])  # Accessing a dictionary value

4. How to Use Lists:

my_list = [1, 2, 3, 4]
print(my_list[0])  # Accessing list elements
my_list.append(5)  # Appending to a list

5. if/elif/else:

# an if/elif/else statement
x = 10
if x > 10:
    print("x is greater than 10")
elif x == 10:
    print("x is equal to 10")
else:
    print("x is less than 10")
    
# or just an if statement
if x == 10:
	print("x is 10")

# or an if/else statement
if x < 10:
	print("x is less than 10")
else:
	print("x is equal to or greater than 10")

6. for Loops:

# iterate over a range
for i in range(5):
    print(i)  # Prints numbers from 0 to 4

# or iterate over a list
list_of_items = ["some item", "some other item"]
for item in items:
	print(item)
	
# or iterate over a dictionary
some_dictionary = {
	"some key": "some value"
}
for key, val in some_dictionary.items():
	print(key, val)

7. while Loops:

count = 0
while count < 5:
    print(count)  # Prints numbers from 0 to 4
    count += 1    # always be sure to increment 
                  # your counter to avoid an infinite loop 

8. Ranges:

# Creates a range from 0 to 4 (exclusive of 5)
my_range = range(5)
for i in my_range:
    print(i)
    
# creates a range from 2 to 10, exclusive of 11, stepping by 2
my_even_range = range(2, 11, 2)
for num in my_even_range:
	print(num)

9. Built-in Methods, String Manipulation, List Manipulation:

my_string = "Hello, World!"
length = len(my_string)  # Get the length of a string
substring = my_string[0:5]  # Get a substring using slice shorthand
my_list = [1, 2, 3]
my_list.append(4)  # Appending to a list

10. How to Use Return in a Function:

# always returning something, otherwise the function will return None by default
def add_numbers(x, y):
    result = x + y
    return result

sum_result = add_numbers(5, 3)  # Calling the function and storing the result