'Executes a BigQuery query, and returns the job ID.
:param operation: The query to execute.
:type operation: string
:param parameters: Parameters to substitute into the query.
:type parameters: dict'

def execute(self, operation, parameters=None):

    bql = (_bind_parameters(operation, parameters) if parameters else operation)
    self.job_id = self.run_query(bql)
