code: def __import_vars(self, env_file):
          
          with open(env_file, "r") as f:  # pylint: disable=invalid-name
              for line in f:
                  try:
                      line = line.lstrip()
                      if line.startswith('export'):
                          line = line.replace('export', '', 1)
                      key, val = line.strip().split('=', 1)
                  except ValueError:  # Take care of blank or comment lines
                      pass
                  else:
                      if not callable(val):
                          if self.verbose_mode:
                              if key in self.app.config:
                                  print(
                                      " * Overwriting an existing config var:"
                                      " {0}".format(key))
                              else:
                                  print(
                                      " * Setting an entirely new config var:"
                                      " {0}".format(key))
                          self.app.config[key] = re.sub(
                              r"\A[\"']|[\"']\Z", "", val)
docs: Actual importing function.