code: def jira_connection(config):
      
      global _jira_connection
      if _jira_connection:
          return _jira_connection
      else:
          jira_options = {'server': config.get('jira').get('url')}
  
          cookies = configuration._get_cookies_as_dict()
          jira_connection = jira_ext.JIRA(options=jira_options)
          session = jira_connection._session
  
          reused_session = False
  
          if cookies:
              requests.utils.add_dict_to_cookiejar(session.cookies, cookies)
              try:
                  jira_connection.session()
                  reused_session = True
              except Exception:
                  pass
  
          if not reused_session:
              session.auth = (config['jira']['username'], base64.b64decode(config['jira']['password']))
              jira_connection.session()
              session.auth = None
  
              cookie_jar_hash = requests.utils.dict_from_cookiejar(session.cookies)
              for key, value in cookie_jar_hash.iteritems():
                  configuration._save_cookie(key, value)
  
          _jira_connection = jira_connection
          return _jira_connection
docs: Gets a JIRA API connection.  If a connection has already been created the existing connection
      will be returned.