parameters: (self, cluster_name)
return_statement: return ClusterModel.query.filter_by(cluster_name=cluster_name).one_or_none()
docstring: Fetches a cluster object from the DB
          :param cluster_id: cluster name 
          :return:
docstring_summary: Fetches a cluster object from the DB
          :param cluster_id: cluster name 
          :return:
docstring_tokens: Fetches a cluster object from the DB : param cluster_id : cluster name : return :
function: def get_by_id(self, cluster_name):
          """
          Fetches a cluster object from the DB
          :param cluster_id: cluster name 
          :return:
          """
          return ClusterModel.query.filter_by(cluster_name=cluster_name).one_or_none()
function_tokens: def get_by_id ( self , cluster_name ) : return ClusterModel . query . filter_by ( cluster_name = cluster_name ) . one_or_none ( )