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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 add_record(self, common_name, serial=0, parent_ca='', signees=None, files=None, record=None, is_ca=False, overwrite=False):
 """Manually create a record of certs Generally, Certipy can be left to manage certificate locations and storage, but it is occasionally useful to keep track of a set of certs that were created externally (for example, let's encrypt) """


        if not overwrite:
            try:
                self.get_record(common_name)
                raise CertExistsError(
                    "Certificate {name} already exists!"
                    " Set overwrite=True to force add."
                    .format(name=common_name))
            except CertNotFoundError:
                pass

        record = record or {
            'serial': serial,
            'is_ca': is_ca,
            'parent_ca': parent_ca,
            'signees': signees,
            'files': files,
        }
        self.store[common_name] = record
        self.save()