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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 max_cation_removal(self):
 """ Maximum number of cation A that can be removed while maintaining charge-balance. Returns: integer amount of cation. Depends on cell size (this is an 'extrinsic' function!) """


        # how much 'spare charge' is left in the redox metals for oxidation?
        oxid_pot = sum(
            [(Element(spec.symbol).max_oxidation_state - spec.oxi_state) * self.comp[spec] for spec
             in self.comp if is_redox_active_intercalation(Element(spec.symbol))])

        oxid_limit = oxid_pot / self.cation_charge

        #the number of A that exist in the structure for removal
        num_cation = self.comp[Specie(self.cation.symbol, self.cation_charge)]

        return min(oxid_limit, num_cation)