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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_dimension_by_unit_measure_or_abbreviation(measure_or_unit_abbreviation,**kwargs):
 """ Return the physical dimension a given unit abbreviation of a measure, or the measure itself, refers to. The search key is the abbreviation or the full measure """


    unit_abbreviation, factor = _parse_unit(measure_or_unit_abbreviation)

    units = db.DBSession.query(Unit).filter(Unit.abbreviation==unit_abbreviation).all()

    if len(units) == 0:
        raise HydraError('Unit %s not found.'%(unit_abbreviation))
    elif len(units) > 1:
        raise HydraError('Unit %s has multiple dimensions not found.'%(unit_abbreviation))
    else:
        dimension = db.DBSession.query(Dimension).filter(Dimension.id==units[0].dimension_id).one()
        return str(dimension.name)