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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 refactor_use_function(self, offset):
 """Use the function at point wherever possible."""

        try:
            refactor = UseFunction(self.project, self.resource, offset)
        except RefactoringError as e:
            raise Fault(
                'Refactoring error: {}'.format(e),
                code=400
            )
        return self._get_changes(refactor)