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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 deserialize(self):
 """ Based on a text based representation of an RSA key this method instantiates a cryptography.hazmat.primitives.asymmetric.rsa.RSAPrivateKey or RSAPublicKey instance """


        # first look for the public parts of a RSA key
        if self.n and self.e:
            try:
                numbers = {}
                # loop over all the parameters that define a RSA key
                for param in self.longs:
                    item = getattr(self, param)
                    if not item:
                        continue
                    else:
                        try:
                            val = int(deser(item))
                        except Exception:
                            raise
                        else:
                            numbers[param] = val

                if 'd' in numbers:
                    self.priv_key = rsa_construct_private(numbers)
                    self.pub_key = self.priv_key.public_key()
                else:
                    self.pub_key = rsa_construct_public(numbers)
            except ValueError as err:
                raise DeSerializationNotPossible("%s" % err)

        if self.x5c:
            _cert_chain = []
            for der_data in self.x5c:
                _cert_chain.append(der_cert(base64.b64decode(der_data)))

            if self.x5t:  # verify the cert thumbprint
                if isinstance(self.x5t, bytes):
                    _x5t = self.x5t
                else:
                    _x5t = self.x5t.encode('ascii')
                if _x5t != x5t_calculation(self.x5c[0]):
                    raise DeSerializationNotPossible(
                        "The thumbprint 'x5t' does not match the certificate.")

            if self.pub_key:
                if not rsa_eq(self.pub_key, _cert_chain[0].public_key()):
                    raise ValueError(
                        'key described by components and key in x5c not equal')
            else:
                self.pub_key = _cert_chain[0].public_key()

            self._serialize(self.pub_key)
            if len(self.x5c) > 1:  # verify chain
                pass

        if not self.priv_key and not self.pub_key:
            raise DeSerializationNotPossible()