code: def prepare_environment(default_settings=_default_settings, **kwargs):
      # pylint: disable=unused-argument
      '''
      Prepare ENV for web-application
      :param default_settings: minimal needed settings for run app
      :type default_settings: dict
      :param kwargs: other overrided settings
      :rtype: None
      '''
      for key, value in default_settings.items():
          os.environ.setdefault(key, value)
      os.environ.update(kwargs)
      if six.PY2:  # nocv
          warnings.warn(
              'Python 2.7 is deprecated and will dropped in 2.0, use Python >3.5',
              DeprecationWarning
          f prepare_environment(default_settings=_default_settings, **kwargs):
      # pylint: disable=unused-argument
      '''
      Prepare ENV for web-application
      :param default_settings: minimal needed settings for run app
      :type default_settings: dict
      :param kwargs: other overrided settings
      :rtype: None
      '''
      for key, value in default_settings.items():
          os.environ.setdefault(key, value)
      os.environ.update(kwargs)
      if six.PY2:  # nocv
          warnings.warn(
              'Python 2.7 is deprecated and will dropped in 2.0, use Python >3.5',
              DeprecationWarning
          )
docs: Prepare ENV for web-application
      :param default_settings: minimal needed settings for run app
      :type default_settings: dict
      :param kwargs: other overrided settings
      :rtype: None