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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 _mpl_ax_to(self, mplobj, output='vb'):
 """Helper to get the parent axes of a given mplobj"""

        for ax in self._axs.values():
            if ax['ax'] is mplobj.axes:
                return ax[output]
        raise RuntimeError('Parent axes could not be found!')