Class to represent a iteration number

version.py

"""
Class to represent a iteration number as a tuple 
ie, it-39.1-130956 is represented as (39,1,130956)
"""

import re
import collections

def cast_parts(parts):
    for part in parts:
        try:
            yield int(part)
        except ValueError:
            yield part
        except TypeError:
            yield 0

class Version(collections.namedtuple('Version', ['major', 'minor', 'change'])):
    __slots__ = ()
    def __new__(cls, version):
        m = re.search(r'it-([0-9]+)\.([0-9]+)(?:-([A-Z0-9]+))?', version)
        self = cls._make(cast_parts(m.groups()))
        return self

# test:
a = Version('it-39.1-130956')
b = Version('it-36.2')

# can now do comparisons
assert(a>b)