def __init__(self, dbconn=None):
        dict.__init__(self)
        self.dbconn = dbconn
        if dbconn:
            self._from_catalog()
Update a constraint.
dataset/ETHPy150Open perseas/Pyrseas/pyrseas/dbobject/__init__.py/DbObjectDict.__init__--crossover with--dataset/ETHPy150Open glue-viz/glue/glue/core/fitters.py/BaseFitter1D.set_constraint