code: def __get_user_data_count(self, sequences):
      length = None
      for sequence in sequences:
          if sequence is not None:
              length = len(sequence)
              break
      return length
  
imports: from bias_detector.BiasMetric import BiasMetric
  from bias_detector.BiasReport import BiasReport
  from bias_detector.models.FirstNameModel import FirstNameModel
  from bias_detector.models.FirstNameZipcodeModel import FirstNameZipcodeModel
  from bias_detector.models.FullNameModel import FullNameModel
  from bias_detector.models.FullNameZipcodeModel import FullNameZipcodeModel
  from bias_detector.bias_metrics.BiasMetricImpl import BiasMetricImpl
  from bias_detector.bias_metrics.BiasMetricInput import BiasMetricInput
  from bias_detector.bias_metrics.FprDiff import FprDiff
  from bias_detector.bias_metrics.PositivePredProbDiff import PositivePredProbDiff
  from bias_detector.bias_metrics.TprDiff import TprDiff
  from bias_detector.common import *
  import surgeo
label_desc: Use image node_id 9 for calling the BiasDetector obj's underlying member method code with example usage: obj.__get_user_data_count(sequences) and returns: length