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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 resolve_id(resolver, identifier, name='object'):
 """Resolves a single id using a resolver function. :param resolver: function that resolves ids. Should return None or a list of ids. :param string identifier: a string identifier used to resolve ids :param string name: the object type, to be used in error messages """

    try:
        return int(identifier)
    except ValueError:
        pass  # It was worth a shot

    ids = resolver(identifier)

    if len(ids) == 0:
        raise exceptions.CLIAbort("Error: Unable to find %s '%s'" % (name, identifier))

    if len(ids) > 1:
        raise exceptions.CLIAbort(
            "Error: Multiple %s found for '%s': %s" %
            (name, identifier, ', '.join([str(_id) for _id in ids])))

    return ids[0]