using for loop to create list

Question

Why this statement does not execute?
>>>y=[for i in range(5)]
SyntaxError: invalid syntax

Why below statement executes without an error?
>>> y=[str(i)for i in range(5)]
>>> print(y)
['0', '1', '2', '3', '4']

Answer 1

y = [i for i in range(5)] is how the first statement should be.

it can also be written as y = list(range(5)) since range returns a generator.

Answer 2

does that 'i' before 'for' corresponds to the element which will be created by the values given by for loop