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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 _collect_valid_settings(meta, clsdict):
 """ Return a sequence containing the enumeration values that are valid assignment values. Return-only values are excluded. """

        enum_members = clsdict['__members__']
        valid_settings = []
        for member in enum_members:
            valid_settings.extend(member.valid_settings)
        clsdict['_valid_settings'] = valid_settings