Return statement

• Consits of the return keyword and an expression
• when the return stement executes, it exits the function
• to end a function
• send the result back to the caller

def f(p1,p2):
    return expression

x = f(arg1, arg2)

• Send expression back to the caller.

Implied Return Statement

• Functions without return stament implicetly return a None it is the equivalent of returning a non-value. This makes it act like a procedure.
• Makes a function act like a procedure
• Examples include print(), sort() method

=> the difference between a function and procedures (in most cases functions provide more flexibility)

# procedure
def cube1(n):
    print(n*n*n)

cube1(10)

# adding two cube results
cube1(2)+cube1(5)
# Output
# TypeError
n1 = cube1(2)
n2 = cube1(5)
print(n1)
# Output
None

You can avoid this with a function

# function

def cube2(n):
    return n*n*n
    # instead of printing an expression will return it by using return
n1 = cube2(2)
n2 = cube2(5)
n1+n2
# Output
# 133

# same result for 
cube2(2) + cube2(5)

• use the procedure if you don’t need the return value.