title: python: locale.Error: unsupported locale setting
body: <p>my code has:</p>
  
  <pre><code>def sep(num, lang='en', none_is_zero=False):
      if num is None:
          if none_is_zero is False:
              return None
          else:
              return 0
      try:
          locale.setlocale(locale.LC_ALL, lang)
      except locale.Error:
          locale.setlocale(locale.LC_ALL, 'en')
      return locale.format("%d", num, grouping=True)
  </code></pre>
  
  <p>since i was getting that error i tried to run this to test:</p>
  
  <pre><code>def test(bot, job):
      print(sep(12343, 'it'))
      print(sep(11425, 'en'))
      print(sep(1234235, None))
      print(sep(42345, ''))
      print(sep(2353636, 'gergreh'))
      print(sep(None, None))
  </code></pre>
  
  <p>and i get this error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "/home/**/utils.py", line 192, in sep
      locale.setlocale(locale.LC_ALL, lang)
    File "/usr/lib/python3.5/locale.py", line 594, in setlocale
      return _setlocale(category, locale)
  locale.Error: unsupported locale setting
  
  During handling of the above exception, another exception occurred:
  
  Traceback (most recent call last):
    File "/usr/local/lib/python3.5/dist-packages/telegram/ext/jobqueue.py", line 286, in tick
      job.run(self.bot)
    File "/usr/local/lib/python3.5/dist-packages/telegram/ext/jobqueue.py", line 411, in run
      self.callback(bot, self)
    File "/home/**/utils.py", line 199, in test
      print(sep(12343, 'it'))
    File "/home/**/utils.py", line 194, in sep
      locale.setlocale(locale.LC_ALL, 'en')
    File "/usr/lib/python3.5/locale.py", line 594, in setlocale
      return _setlocale(category, locale)
  locale.Error: unsupported locale setting
  </code></pre>
  
  <p>but i don't get any error on windows and the function works as expected. The problem is only on my ubuntu vps.
  finding some answers on stackoverflow i saw someone suggesting to use 'en_US.UTF-8' and i tried and it works even on linux. But 'en.UTF-8' still doesn't work. i could append <code>UTF-8</code> if it's needed but the api i use sometimes returns as lang_code only 'en', 'it', 'es'.</p>
  
  <p>how can i get rid of this problem? on windows i don't have problems and it seems like the problem is just my linux vps with <code>it</code>, <code>en</code> etc</p>