confused

So to answer your question, basically, anything with parenthesis is a function. "if", "del", "in" are statements and not exactly the same as functions.

Functions are things that takes in arguments, some examples:

print('hello world')
int('1234567')
range(1,5)

the way a function is created is using the "def" statement. Notice again that def is a keyword and a statement but it's not a function in itself.

a function can be thought of for now as a bunch of statements combined together.

so going back to how a function is created, we start with "def" and then we name the function as such:

def printer(something):

what this did is created a function printer that takes an argument, "something". That allows us to use this function you created later without writing the code again like this:

printer(5)
printer(6)
printer(7)

But the problem is that right now, our defined function, printer doesn't do anything, since there's nothing inside the function.

to do so, we have to take our function and add what we want to do to it, like this:

def printer(something):
    print(something * "Hi ")

notice that something inside the printer function matches exactly with the word something inside the print function. This is a variable that means print("whatever number the person typed" * "Hi "), so continuing from the above example,

printer(5)
# gets translated by the function into:
print(5 * "Hi ")
Hi Hi Hi Hi Hi 


printer(6)
# gets translated by the function into:
print(6 * "Hi ")
Hi Hi Hi Hi Hi Hi 


printer(7)
# gets translated by the function into:
print(7 * "Hi ")
Hi Hi Hi Hi Hi Hi Hi 

notice that once you def the function printer once, all you have to do is type printer(some_number) and you run the function.

I hope this was an easier explanation than the documentations. Keep at it! It gets easy once you understand it!