gistfile1.py

class SampleHighlight(object):
  def __init__(self, job_id, sample_name, field1):
    errors = []
    if not job_id.startswith("JOB_ID"):
      errors.append("STRUCTURAL FAILURE: bad job_id")
      
    try:
      self._check_sample_name(sample_name)
    except Exception as error:
      errors.append(error.message)
    
    # and so on performing any sturctural validation that makes sense 
    # in the context of the abstract object
  
  @staticmethod
  def fromFile(self, filename):
    if not os.isfile(filename):
      raise Exception("STRUCTURAL ERROR: can't read file")
      
    with open(filename) as file_to_read:
      try:
        job_id = line[0][1]
      except KeyError as error:
        raise Exception("STRUCTURAL ERROR: expected a job id")
      
      # etc try except blocks for the rest of the things to pass strcutural validation
      sample_name = filename
      field1 = line[1]
      return SampleHighlight(job_id, sample_name, field1)