[Python] Using filter function and convert the iterator produce to a list [closed]

Here is something I stumbled upon. I have this little class.

from functools import reduce

class CourseAttempt:
def __init__(self, course_name: str, grade: int, credits: int):
self.course_name = course_name
self.grade = grade
self.credits = credits

def __str__(self):
return f"{self.course_name} ({self.credits} cr) grade {self.grade}"


Then these two code snippets

course_passed = list(filter(lambda x: x.grade >= 1, attempts))
print(course_passed)


and

course_passed = filter(lambda x: x.grade >= 1, attempts)
course_passed_list = list(course_passed)
print(course_passed_list)


I'm trying to filter a list of students called 'attempts' with grade >= 1 then convert the iterator produced by the filter function into a list before printing. The first code snippet does exactly what I want meanwhile the second do not. Can anyone explain to me why these two operation do no produce the same result?

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