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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_entity_propnames(entity):
 """ Get entity property names :param entity: Entity :type entity: sqlalchemy.ext.declarative.api.DeclarativeMeta :returns: Set of entity property names :rtype: set """

    ins = entity if isinstance(entity, InstanceState) else inspect(entity)
    return set(
        ins.mapper.column_attrs.keys() +  # Columns
        ins.mapper.relationships.keys()  # Relationships
    )