Locale problem in GNU/Linux

[approximatenumber]

OS: GNU/Linux Debian 9
Python: 3.6
Django: 2.1.5

Error:

Traceback (most recent call last):
  File "./parser.py", line 15, in <module>
    locale.setlocale(locale.LC_TIME, "ru_RU")
  File "/usr/local/lib/python3.6/locale.py", line 598, in setlocale
    return _setlocale(category, locale)
locale.Error: unsupported locale setting