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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 exists_dimension(dimension_name,**kwargs):
 """ Given a dimension returns True if it exists, False otherwise """

    try:
        dimension = db.DBSession.query(Dimension).filter(Dimension.name==dimension_name).one()
        # At this point the dimension exists
        return True
    except NoResultFound:
        # The dimension does not exist
        raise False