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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 get_mnemonics(self, mnemonics, uwis=None, alias=None):
 """ Looks at all the wells in turn and returns the highest thing in the alias table. Args: mnemonics (list) alias (dict) Returns: list. A list of lists. """

        # Let's not do the nested comprehension...
        uwis = uwis or self.uwis
        wells = [w for w in self.__list if w.uwi in uwis]
        all_wells = []
        for w in wells:
            this_well = [w.get_mnemonic(m, alias=alias) for m in mnemonics]
            all_wells.append(this_well)
        return all_wells