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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 _proc_dihedral(self):
 """ Handles dihedral group molecules, i.e those with intersecting R2 axes and a main axis. """

        main_axis, rot = max(self.rot_sym, key=lambda v: v[1])
        self.sch_symbol = "D{}".format(rot)
        mirror_type = self._find_mirror(main_axis)
        if mirror_type == "h":
            self.sch_symbol += "h"
        elif not mirror_type == "":
            self.sch_symbol += "d"