Can someone explain to me how this works please??

Question

def cm():
return [lambda x : x*i for I in range(3)]
for m in cm():
print(m(1))

#the output of this code is
>>> 2
>>> 2
>>> 2

I know that this programme defines a function that returns a list of function (its length is given by the range() function) then calls then with the parameter assigned 1, but I don't understand why the output is the same because in the comprehensive list "i" should change when creating those function thus the output should be :
0 #x*0 (i=0)
1 #x*1 (i=1)
2 #x*2 (i=2)

plz help!!!

Answer 1

https://eli.thegreenplace.net/2015/the-scope-of-index-variables-in-pythons-for-loops/

Here the main part is:
def foo():
lst = []
for i in range(4):
lst.append(lambda: i)
print([f() for f in lst])

If you'd expect this to print [0, 1, 2, 3], no such luck. This code will, instead, emit [3, 3, 3, 3], because there's just a single i in the scope of foo, and this is what all the lambdas capture.

Answer 2

'''you must change from a list to a generator
use round ( ) brackets instead of square [ ] brackets
'''
def cm():
return (lambda x : x*i for i in range(3))
for m in cm():
print(m(1))

Answer 3

still didn't quit understand that , if this how it works then why [I for I in range (4)] gives [0,1,2,3] and not [3,3,3,3]

Answer 4

what you expect will result if you will change print(m(m))