code: def sampling_query(sql, context, fields=None, count=5, sampling=None, udfs=None,
                       data_sources=None):
      
      return Query(_sampling.Sampling.sampling_query(sql, fields, count, sampling), context=context,
                   udfs=udfs, data_sources=data_sources)
docs: Returns a sampling Query for the SQL object.
  
      Args:
        sql: the SQL statement (string) or Query object to sample.
        context: a Context object providing project_id and credentials.
        fields: an optional list of field names to retrieve.
        count: an optional count of rows to retrieve which is used if a specific
            sampling is not specified.
        sampling: an optional sampling strategy to apply to the table.
        udfs: array of UDFs referenced in the SQL.
        data_sources: dictionary of federated (external) tables referenced in the SQL.
      Returns:
        A Query object for sampling the table.