Reports

I used lambda because I think the argument of a function had the property of holding a value.

I do not understand the details of the detailed grammatical evaluation with difficulty, but I was able to successfully prepare a generator that generates a generator by doing the following.

root_gen = ((lambda t: ((t,y) for y in range(3)))(x) for x in range(5))

To evaluate, please use below:

tuple(map(tuple, root_gen))

The original idea is as follows:

# generate a sub generator
def sub_gen(x):
    return ((x,y) for y in range(3))

# test 
tuple(gen(1))
tuple(gen(2))

# make generator
root_gen = (gen(n) for n in range(5)) 

# evaluate
tuple(map(tuple(root_gen)))

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