I basically want a python equivalent of this in C:
int a[x];
but in python I declare an array like:
a = []
and the problem is I want to assign random slots with values like:
a[4] = 1
but I can't do that with python, since the array is empty.
If by "array" you actually mean a Python list, you can use
a = [0] * 10
or
a = [None] * 10