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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 _fit_radec(self):
 """ call fit_radec of BK passing in the observations. """


        # call fitradec with mpcfile, abgfile, resfile
        self.orbfit.fitradec.restype = ctypes.c_int
        self.orbfit.fitradec.argtypes = [ ctypes.c_char_p, ctypes.c_char_p, ctypes.c_char_p ]

        mpc_file = tempfile.NamedTemporaryFile(suffix='.mpc')
        for observation in self.observations:
            mpc_file.write("{}\n".format(str(observation)))
        mpc_file.seek(0)

        abg_file = tempfile.NamedTemporaryFile()
        res_file = tempfile.NamedTemporaryFile()

        self.orbfit.fitradec(ctypes.c_char_p(mpc_file.name),
                             ctypes.c_char_p(abg_file.name),
                             ctypes.c_char_p(res_file.name))

        self.abg = abg_file
        self.abg.seek(0)
        self.residuals = res_file
        self.residuals.seek(0)