Returns metrics and plots writer.

Note, sharding will be enabled by default if a output_file_format is provided. The files will be named -SSSSS-of-NNNNN. where SSSSS is the shard number and NNNNN is the number of shards.

output_paths Output paths keyed by output key (e.g. 'metrics', 'plots', 'validation').
eval_config Eval config.
add_metrics_callbacks Optional list of metric callbacks (if used).
metrics_key Name to use for metrics key in Evaluation output.
plots_key Name to use for plots key in Evaluation output.
attributions_key Name to use for attributions key in Evaluation output.
validations_key Name to use for validations key in Evaluation output.
output_file_format File format to use when saving files. Currently 'tfrecord' and 'parquet' are supported and 'tfrecord is the default'. If using parquet, the output metrics and plots files will contain two columns, 'slice_key' and 'serialized_value'. The 'slice_key' column will be a structured column matching the metrics_for_slice_pb2.SliceKey proto. The 'serialized_value' column will contain a serialized MetricsForSlice or PlotsForSlice proto. The validation result file will contain a single column 'serialized_value' which will contain a single serialized ValidationResult proto.
rubber_stamp True if this model is being rubber stamped. When a model is rubber stamped diff thresholds will be ignored if an associated baseline model is not passed.
stage_name The stage name to use when this writer is added to the Beam pipeline.