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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 _process_schema(self, schema_dict, validators):
 """ Go through a schema and construct validators. """

        schema_flat = util.flatten(schema_dict)

        for key, expression in schema_flat.items():
            try:
                schema_flat[key] = syntax.parse(expression, validators)
            except SyntaxError as e:
                # Tack on some more context and rethrow.
                error = str(e) + ' at node \'%s\'' % key
                raise SyntaxError(error)
        return schema_flat