How to use the wechatpy.utils.to_text function in wechatpy

def test_base64encode_field_to_xml(self):
        from wechatpy.fields import Base64EncodeField

        content = b'test'
        field = Base64EncodeField('Content')
        expected = '<content></content>'.format(
            content=to_text(base64.b64encode(content))
        )
        self.assertEqual(expected, field.to_xml(content))

def get_jsapi_signature(self, prepay_id, timestamp=None, nonce_str=None):
        """
        获取 JSAPI 签名

        :param prepay_id: 统一下单接口返回的 prepay_id 参数值
        :param timestamp: 可选，时间戳，默认为当前时间戳
        :param nonce_str: 可选，随机字符串，默认自动生成
        :return: 签名
        """
        data = {
            'appId': self.sub_appid or self.appid,
            'timeStamp': timestamp or to_text(int(time.time())),
            'nonceStr': nonce_str or random_string(32),
            'signType': 'MD5',
            'package': 'prepay_id={0}'.format(prepay_id),
        }
        return calculate_signature(
            data,
            self._client.api_key if not self._client.sandbox else self._client.sandbox_api_key
        )

def _decrypt(self, text, _id, exception=None):
        text = to_binary(text)
        plain_text = self.cipher.decrypt(base64.b64decode(text))
        padding = byte2int(plain_text[-1])
        content = plain_text[16:-padding]
        xml_length = socket.ntohl(struct.unpack(b'I', content[:4])[0])
        xml_content = to_text(content[4:xml_length + 4])
        from_id = to_text(content[xml_length + 4:])
        if from_id != _id:
            exception = exception or Exception
            raise exception()
        return xml_content

def __repr__(self):
        _repr = '{klass}({code}, {msg}). Pay({pay_code}, {pay_msg})'.format(
            klass=self.__class__.__name__,
            code=self.return_code,
            msg=self.return_msg,
            pay_code=self.errcode,
            pay_msg=self.errmsg
        )
        if six.PY2:
            return to_binary(_repr)
        else:
            return to_text(_repr)

def __str__(self):
        _repr = 'Error code: {code}, message: {msg}'.format(
            code=self.errcode,
            msg=self.errmsg
        )
        if six.PY2:
            return to_binary(_repr)
        else:
            return to_text(_repr)

def get(self, key, default=None):
        key = self.key_name(key)
        value = self.redis.get(key)
        if value is None:
            return default
        return json.loads(to_text(value))

def _decrypt(self, text, _id, exception=None):
        text = to_binary(text)
        plain_text = self.cipher.decrypt(base64.b64decode(text))
        padding = byte2int(plain_text[-1])
        content = plain_text[16:-padding]
        xml_length = socket.ntohl(struct.unpack(b'I', content[:4])[0])
        xml_content = to_text(content[4:xml_length + 4])
        from_id = to_text(content[xml_length + 4:])
        if from_id != _id:
            exception = exception or Exception
            raise exception()
        return xml_content

def create(self, name):
        """
        创建分组

        详情请参考
        http://mp.weixin.qq.com/wiki/0/56d992c605a97245eb7e617854b169fc.html

        :param name: 分组名字（30个字符以内）
        :return: 返回的 JSON 数据包

        """
        name = to_text(name)
        return self._post(
            'groups/create',
            data={'group': {'name': name}}
        )

def _encrypt_message(self,
                         msg,
                         nonce,
                         timestamp=None,
                         crypto_class=None):
        from wechatpy.replies import BaseReply

        xml = """


{timestamp}

"""
        if isinstance(msg, BaseReply):
            msg = msg.render()
        timestamp = timestamp or to_text(int(time.time()))
        pc = crypto_class(self.key)
        encrypt = to_text(pc.encrypt(msg, self._id))
        signature = _get_signature(self.token, timestamp, nonce, encrypt)
        return to_text(xml.format(
            encrypt=encrypt,
            signature=signature,
            timestamp=timestamp,
            nonce=nonce
        ))