python-防止在ipython shell中显示调试日志信息

我在virtualenv中使用scrapy shell。IPython安装在virtualenv内部。当我开始使用scrapy shell时

 scrapy shell 'https://example.com'

按tab键可获得自动完成建议，它会显示大量调试信息。如何禁用此功能？

In [1]: from scra2018-03-23 10:05:45 [parso.python.diff] DEBUG: diff parser start
2018-03-23 10:05:45 [parso.python.diff] DEBUG: diff parser calculated
2018-03-23 10:05:45 [parso.python.diff] DEBUG: diff: line_lengths old: 1, new: 1
2018-03-23 10:05:45 [parso.python.diff] DEBUG: diff replace old[1:1] new[1:1]
2018-03-23 10:05:45 [parso.python.diff] DEBUG: parse_part from 1 to 1 (to 0 in part parser)
2018-03-23 10:05:45 [parso.python.diff] DEBUG: diff parser end