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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 _dx(self):
 """Return integer width of this shape's path in local units."""

        min_x = max_x = self._start_x
        for drawing_operation in self:
            if hasattr(drawing_operation, 'x'):
                min_x = min(min_x, drawing_operation.x)
                max_x = max(max_x, drawing_operation.x)
        return max_x - min_x