def does_disk_exist(self, parameters, disk_name):
    conn = self.open_connection(parameters)
    try:
      conn.get_all_volumes([disk_name])
      AppScaleLogger.log('EBS volume {0} does exist'.format(disk_name))
      return True
    except boto.exception.EC2ResponseError:
      AppScaleLogger.log('EBS volume {0} does not exist'.format(disk_name))
      return False
Returns a custom url to add plugin instances
dataset/ETHPy150Open AppScale/appscale-tools/lib/agents/ec2_agent.py/EC2Agent.does_disk_exist--crossover with--dataset/ETHPy150Open divio/django-cms/cms/models/pluginmodel.py/CMSPlugin.add_url