[python] List append() in for loop

In Python, trying to do the most basic append function to a list with a loop: Not sure what i am missing here:

a=[]
for i in range(5):    
    a=a.append(i)
a

returns: 'NoneType' object has no attribute 'append'

No need to re-assign.

a=[]
for i in range(5):    
    a.append(i)
a

You don't need the assignment, list.append(x) will always append x to a and therefore there's no need te redefine a.

a = []
for i in range(5):    
    a.append(i)
print(a)

is all you need. This works because lists are mutable.

Also see the docs on data structures.