text: """Module with class representing common API."""
  import requests
  
  
  class Api:
      """Class representing common API."""
  
      _API_ENDPOINT = 'api/v1'
  
      def __init__(self, url, token=None):
          """Set the API endpoint and store the authorization token if provided."""
          self.url = Api.add_slash(url)
          self.token = token
  
      def is_api_running(self):
          """Check if the API is available for calls."""
          try:
              res = requests.get(self.url)
              if res.status_code in {200, 401}:
                  return True
          except requests.exceptions.ConnectionError:
              pass
          return False
  
      @staticmethod
      def add_slash(url):
          """Add a slash at end of URL, if the slash is not provided."""
          if url and not url.endswith('/'):
              url += '/'
          return url
  
      def get(self):
          """Use GET method to access API."""
          return requests.get(self.url)
  
      def print_error_response(self, response, message_key):
          """Print error message if anything goes wrong."""
          print("    Server returned HTTP code {c}".format(c=response.status_code))
          error_message = None
          try:
              error_message = response.json().get(message_key, "Server did not sent error message")
          except Exception:
              pass   # no error message
  
          if error_message:
              print("    Error message: {m}".format(m=error_message))
  