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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 calculate_colorbar(self):
 """ Returns the positions and colors of all intervals inside the colorbar. """

        self._base._process_values()
        self._base._find_range()
        X, Y = self._base._mesh()
        C = self._base._values[:, np.newaxis]
        return X, Y, C