code: def collect_data(parent_module):
      
  
      data = dict()
      for file_meta in parent_module.find_log_files('picard/variant_calling_metrics', filehandles=True):
          s_name = None
          for header, value in table_in(file_meta['f'], pre_header_string='## METRICS CLASS'):
              if header == 'SAMPLE_ALIAS':
                  s_name = value
                  if s_name in data:
                      log.debug("Duplicate sample name found in {}! Overwriting: {}".format(file_meta['fn'], s_name))
                  data[s_name] = OrderedDict()
              else:
                  data[s_name][header] = value
      return data
docs: Find Picard VariantCallingMetrics reports and parse their data