docs: def get_api_user_key(self, api_dev_key, username=None, password=None):
          '''
          Get api user key to enable posts from user accounts if username
          and password available.
          Not getting an api_user_key means that the posts will be "guest" posts
          '''
          username = username or get_config('pastebin', 'api_user_name')
          password = password or get_config('pastebin', 'api_user_password')
          if username and password:
              data = {
                  'api_user_name': username,
                  'api_user_password': password,
                  'api_dev_key': api_dev_key,
              }
              urlencoded_data = urllib.urlencode(data)
              req = urllib2.Request('http://pastebin.com/api/api_login.php',
                                    urlencoded_data)
              response = urllib2.urlopen(req)
              user_key = response.read()
              logging.debug("User key: %s" % user_key)
              return user_key
          else:
              logging.info("Pastebin: not using any user key")
              return ""