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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 units(self, value):
 """Set units."""

        if value is None:
            if "units" in self.attrs.keys():
                self.attrs.pop("units")
        else:
            try:
                self.attrs["units"] = value
            except AttributeError:
                self.attrs["units"] = value