Use generator comprehension instead of list comprehension in for loop declaration.

Python generators resemble lazy lists from other programming languages: when iterated over, they compute their values on the fly. They lack some list behaviors (indexing, len method, …​) but are memory-efficient, as they do not store each of their values in memory, unlike lists. Thus, when declared in a for-loop declaration, list comprehensions can be safely replaced with generator comprehensions.

For more details on list comprehensions vs generator comprehensions, see Python documentation.