python 3.2 semi natural sorting

import re

pose_list = "Pose1", "Pose10", "Pose11", "Pose2", "Pose3", "Pose4"
pattern = '\d+'  # one or more numerical characters

# this function assumes list consistency.
def MyFn(pose):
    match = re.search(pattern, pose)
    return int(match.group())

# this returns a sorted list given the presence of a numerical sequence in the string
print(sorted(pose_list, key=MyFn))  

# sorted() now returns ['Pose1', 'Pose2', 'Pose3', 'Pose4', 'Pose10', 'Pose11']

(unfortunately) i think blender will automatically resort that list alphabetically it is advised to add padding zeroes.