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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 get_modification_date(brain_or_object):
 """Get the modification date of the brain or object :param brain_or_object: A single catalog brain or content object :type brain_or_object: ATContentType/DexterityContentType/CatalogBrain :returns: Modification date :rtype: DateTime """

    modified = getattr(brain_or_object, "modified", None)
    if modified is None:
        fail("Object {} has no modification date ".format(
             repr(brain_or_object)))
    if callable(modified):
        return modified()
    return modified