using range in combination with remove is inconsistent.  for example in 
python 2.x:

>>> x = range(0,3)
>>> x.remove(1)
>>> x
[0, 2]
>>> x = range(0,3).remove(1)
>>> x
>>>

and in python 3.x:
>>> x = list(range(0,3))
>>> x.remove(1)
>>> x
[0, 2]
>>> x = list(range(0,3)).remove(1)
>>> x
>>> 

why does the second approach remove all items from the list?

>>> [1,2,3].remove(1)
>>> repr([1,2,3].remove(1))
'None'

The remove method mutates the list, and therefore like all such mutating
methods, it returns None.

ok, i see now.  the list itself is changed in place, and the return value 
of the remove() method is always None.  since i din't assign the list to a 
variable in the first place, there is hence no way now to access that 
modified list.

thanks for your help.