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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def version_diff(version1, version2):
 """Return string representing the diff between package versions. We're interested in whether this is a major, minor, patch or 'other' update. This method will compare the two versions and return None if they are the same, else it will return a string value indicating the type of diff - 'major', 'minor', 'patch', 'other'. Args: version1: the Version object we are interested in (e.g. current) version2: the Version object to compare against (e.g. latest) Returns a string - 'major', 'minor', 'patch', 'other', or None if the two are identical. """

    if version1 is None or version2 is None:
        return 'unknown'
    if version1 == version2:
        return 'none'

    for v in ('major', 'minor', 'patch'):
        if getattr(version1, v) != getattr(version2, v):
            return v

    return 'other'