Flexget: missing python-telegram-bot pkg

Expected behaviour:

Send a message to one or more Telegram users or groups upon accepting a download.

Actual behaviour:

missing python-telegram-bot pkg

Steps to reproduce:

• Step 1: http://flexget.com/wiki/Plugins/send_telegram
• Step 2: Renamed telegram : http://flexget.com/wiki/Plugins/telegram

so I changed send_telegram to telegram.

Config:

paste relevant config
use paste service if config is too long

Log:

2016-06-30 00:04 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:04 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:05 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:06 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:06 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:06 WARNING  plugin        task      missing python-telegram-bot pkg
2016-06-30 00:06 WARNING  plugin        task      missing python-telegram-bot pkg

Additional information:

• Flexget Version:

/usr/local/flexget/env/bin/flexget -V
2.1.3
You are on the latest release.

• Python Version: 2.7.9
• python-telegram-bot Version : 4.3.1
• OS and version: Synology DSM
• Link to crash log: