Why is this generator not working in Python?

Question

I am trying to return all product reviews by user name.

I have written a generator function but on coming back to it, it does not work and returns a syntax error:



def find_reviews(username):
    for u in reviewers_dicts:
        if u['username'] == username:
            review = u['reviews']
            yield review
            print(review)
            next

find_reviews('krpz1113')

I am getting the following error:

<generator object find_reviews at 0x0000016C852CECF0>

That's not an error, if you want to see the result encapsulate it in `list()` — Robin Dillen, Jan 16 '22 at 17:07
That's how generator works. Its not the error, rather the object. you can get the result `next(find_reviews)` — Irfanuddin, Jan 16 '22 at 17:08
the output you show does not match the code snippet. That is representation of generator object being printed. — buran, Jan 16 '22 at 17:12
@buran The Python shell outputs the return objects of functions if you call them, so the user could have typed this code into the Python shell. — Sylvester Kruin, Jan 16 '22 at 17:16
@SylvesterKruin, if this is the case there would be `>>>` and `...` in the code and we should not be asked to guess (do you really think they removed the `>>>`?). In any case, the code snippet is incomplete - `reviewers_dicts` is not present. — buran, Jan 16 '22 at 17:19
btw, that bare `next` after `print(review)` makes no sense and does nothing — juanpa.arrivillaga, Jan 16 '22 at 18:02

score 2 · Answer 1 · answered Jan 16 '22 at 17:24

<generator object find_reviews at 0x0000016C852CECF0> Is not an error, but a generator object (As it says in the output). To get your desired result, you can use next(). For example:

def func(x):
    num = 0
    while num < x:
        yield num
        num += 1
b = func(10)
# Use these to get an individual value
next(b) 
next(b)

Output:

0
1

Alternatively, you can call the list method on your generator object:

def func(x):
    num = 0
    while num < x:
        yield num
        num += 1
b = func(10)
# Use this to get a list
lst = list(b)
print(lst)

or iterate through a for loop:

def func(x):
    num = 0
    while num < x:
        yield num
        num += 1
b = func(10)

for item in b:
    print(item)

Why is this generator not working in Python?

1 Answers1