Python rotate/shift a sub-list along an input list

rotateSubList.py

# This function rotates a sublist of a list, given a starting position and a length. Position can be incremented infinitely.
def rotateSubList(bigList, position, length):
    # We check if the left index is still smaller than the right index after the modulo operation.
    if position % len(bigList) < (position+length) % len(bigList):
        # The order is preserved, so we can safely use the slice notation
        return bigList[position%len(bigList): (position+length)%len(bigList)]
    else:
        # The order is NOT preserved. The resulting array would have been clamped to the right by the slice notation.
        # We add the missing part, sourced from the start of the bigList.
        return bigList[position%len(bigList): len(bigList)] + bigList[0: (position+length)%len(bigList)]

# For example:
# a = [0,1,3,4,5,6,7,8,9,10]
# rotateSubList(a, 3, 5) returns [4, 5, 6, 7, 8]
# rotateSubList(a, 4, 5) returns [5, 6, 7, 8, 9]
# [...]
# rotateSubList(a, 7, 5) returns [8, 9, 10, 0, 1]