code: def convert_multidim_measurements(all_phases):
    
    # Combine actual attachments with attachments we make from multi-dim
    # measurements.
    attachment_names = list(itertools.chain.from_iterable(
        phase.attachments.keys() for phase in all_phases))
    attachment_names.extend(itertools.chain.from_iterable([
        'multidim_' + name for name, meas in phase.measurements.items()
        if meas.dimensions is not None
    ] for phase in all_phases if phase.measurements))
    attachment_name_maker = UniqueNameMaker(attachment_names)
  
    for phase in all_phases:
      # Process multi-dim measurements into unique attachments.
      for name, measurement in sorted(phase.measurements.items()):
        if measurement.dimensions:
          old_name = name
          name = attachment_name_maker.make_unique('multidim_%s' % name)
          attachment = multidim_measurement_to_attachment(name, measurement)
          phase.attachments[name] = attachment
          phase.measurements.pop(old_name)
    return all_phases
docs: Converts each multidim measurements into attachments for all phases..