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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 buscar(self, id_vlan):
 """Get VLAN by its identifier. :param id_vlan: VLAN identifier. :return: Following dictionary: :: {'vlan': {'id': < id_vlan >, 'nome': < nome_vlan >, 'num_vlan': < num_vlan >, 'id_ambiente': < id_ambiente >, 'id_tipo_rede': < id_tipo_rede >, 'rede_oct1': < rede_oct1 >, 'rede_oct2': < rede_oct2 >, 'rede_oct3': < rede_oct3 >, 'rede_oct4': < rede_oct4 >, 'bloco': < bloco >, 'mascara_oct1': < mascara_oct1 >, 'mascara_oct2': < mascara_oct2 >, 'mascara_oct3': < mascara_oct3 >, 'mascara_oct4': < mascara_oct4 >, 'broadcast': < broadcast >, 'descricao': < descricao >, 'acl_file_name': < acl_file_name >, 'acl_valida': < acl_valida >, 'ativada': < ativada >} OR {'id': < id_vlan >, 'nome': < nome_vlan >, 'num_vlan': < num_vlan >, 'id_tipo_rede': < id_tipo_rede >, 'id_ambiente': < id_ambiente >, 'bloco1': < bloco1 >, 'bloco2': < bloco2 >, 'bloco3': < bloco3 >, 'bloco4': < bloco4 >, 'bloco5': < bloco5 >, 'bloco6': < bloco6 >, 'bloco7': < bloco7 >, 'bloco8': < bloco8 >, 'bloco': < bloco >, 'mask_bloco1': < mask_bloco1 >, 'mask_bloco2': < mask_bloco2 >, 'mask_bloco3': < mask_bloco3 >, 'mask_bloco4': < mask_bloco4 >, 'mask_bloco5': < mask_bloco5 >, 'mask_bloco6': < mask_bloco6 >, 'mask_bloco7': < mask_bloco7 >, 'mask_bloco8': < mask_bloco8 >, 'broadcast': < broadcast >, 'descricao': < descricao >, 'acl_file_name': < acl_file_name >, 'acl_valida': < acl_valida >, 'acl_file_name_v6': < acl_file_name_v6 >, 'acl_valida_v6': < acl_valida_v6 >, 'ativada': < ativada >}} :raise VlanNaoExisteError: VLAN does not exist. :raise InvalidParameterError: VLAN id is none or invalid. :raise DataBaseError: Networkapi failed to access the database. :raise XMLError: Networkapi failed to generate the XML response. """

        if not is_valid_int_param(id_vlan):
            raise InvalidParameterError(
                u'Vlan id is invalid or was not informed.')

        url = 'vlan/' + str(id_vlan) + '/'

        code, xml = self.submit(None, 'GET', url)

        return self.response(code, xml)