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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 _serializer(obj):
    '''
    helper function to serialize some objects for prettier return
    '''
    import datetime
    if isinstance(obj, datetime.datetime):
        if obj.utcoffset() is not None:
            obj = obj - obj.utcoffset()
        return obj.__str__()
    return obj