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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 _apply_mapping(self, mapping):
 """ Map some case specific data to the fields in internal dictionary. """

        self._POST["P0100LDR__"] = mapping[0]
        self._POST["P0200FMT__"] = mapping[1]
        self._POST["P0300BAS__a"] = mapping[2]
        self._POST["P07022001_b"] = mapping[3]
        self._POST["P1501IST1_a"] = mapping[4]