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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 set_constants(self, *constants, verbose=True):
 """Set the constants associated with the data. Parameters constants : str Expressions for the new set of constants. verbose : boolean (optional) Toggle talkback. Default is True See Also -------- transform Similar method except for axes. create_constant Add an individual constant. remove_constant Remove an individual constant. """

        # create
        new = []
        current = {c.expression: c for c in self._constants}
        for expression in constants:
            constant = current.get(expression, Constant(self, expression))
            new.append(constant)
        self._constants = new
        # units
        for c in self._constants:
            if c.units is None:
                c.convert(c.variables[0].units)
        # finish
        self.flush()
        self._on_constants_updated()