Creating a function in Python involves the def keyword, the function name, parentheses ( ), and a colon (:). The code for the function is then indented under the function definition. Here is an example:
```
def hello_world(): # This is the function definition
print(“Hello, world!”) # This is the function body
hello_world() # This is how to call the function
```
In this example, the function hello\_world() takes no arguments and simply prints out “Hello, world!”. The function is then called using its name followed by parentheses.
Functions can also take parameters (also known as arguments), which are specified in the parentheses. For example, here’s a function that takes a name as an argument and prints a greeting:
```
def greet(name): # name is the parameter
print(“Hello, “ + name + “!”)
greet(“Alice”) # “Alice” is the argument
```
In this example, calling greet(“Alice”) will print out “Hello, Alice!”.
To return a value from a function, use the return keyword:
```
def add(a, b):
return a + b
result = add(3, 4)
print(result) # prints: 7
```
This add() function takes two parameters, adds them together, and returns the result. The returned value can then be used as needed.
Indents (spaces or tabs) are important in Python to denote blocks of code under function definitions, if statements, for loops etc.
Remember to call the function once you have defined it, otherwise, the function won’t be executed. You can call a function by typing the function name followed by parentheses and providing necessary arguments (if needed).
