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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 _pmrapmdec(self,*args,**kwargs):
 """Calculate pmra and pmdec"""

        lbdvrpmllpmbb= self._lbdvrpmllpmbb(*args,**kwargs)
        return coords.pmllpmbb_to_pmrapmdec(lbdvrpmllpmbb[:,4],
                                            lbdvrpmllpmbb[:,5],
                                            lbdvrpmllpmbb[:,0],
                                            lbdvrpmllpmbb[:,1],degree=True,
                                            epoch=None)