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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_scalar(self, indexer, value):
 """ Set scalar value into the array. Parameters indexer : any The indexer to set the value at. value : str The value to assign at the given locations. Raises ------ ValueError Raised when ``value`` is not a value element of this this label array. """

        try:
            value_code = self.reverse_categories[value]
        except KeyError:
            raise ValueError("%r is not in LabelArray categories." % value)

        self.as_int_array()[indexer] = value_code