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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 _merge_constraints(constraints, overrides):
 """Merge the constraints avoiding duplicates Change constraints in place. """

    for o in overrides:
        i = 0
        while i < len(constraints):
            c = constraints[i]
            if _same(o, c):
                constraints[i].update(o)
                break
            i = i + 1