old_contents: import pytest
  
  RED_DOT = """data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
  AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
  9TXL0Y4OHwAAAABJRU5ErkJggg=="""
  
  @pytest.fixture
  def antibody_characterization(submitter, award, lab, antibody_lot, target):
      return {
          'award': award['uuid'],
          'lab': lab['uuid'],
          'target': target['uuid'],
          'characterizes': antibody_lot['uuid'],
      }
  
  
  def test_antibody_characterization_reviews(testapp, antibody_characterization):
      antibody_characterization['characterization_reviews'] = [ {"organism": "human", "lane": 2, "biosample_type": "immortalized cell line", "biosample_term_name": "K562", "biosample_term_id": "EFO:0002067"}]
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
  def test_antibody_characterizaton_two_methods(testapp, antibody_characterization):
      antibody_characterization['primary_characterization_method'] = 'immunoblot'
      antibody_characterization['secondary_characterization_method'] = 'dot blot assay'
      antibody_characterization['attachment'] =  {'download': 'red-dot.png', 'href': RED_DOT}
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
  def test_antibody_status_wrangler(testapp, antibody_characterization):
      antibody_characterization['primary_characterization_method'] = 'immunoblot'
      antibody_characterization['status'] = 'compliant'
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
new_contents: import pytest
  
  RED_DOT = """data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA
  AAAFCAYAAACNbyblAAAAHElEQVQI12P4//8/w38GIAXDIBKE0DHxgljNBAAO
  9TXL0Y4OHwAAAABJRU5ErkJggg=="""
  
  
  @pytest.fixture
  def antibody_characterization(submitter, award, lab, antibody_lot, target):
      return {
          'award': award['uuid'],
          'lab': lab['uuid'],
          'target': target['uuid'],
          'characterizes': antibody_lot['uuid'],
      }
  
  
  def test_antibody_characterization_reviews(testapp, antibody_characterization):
      antibody_characterization['characterization_reviews'] = [{"organism": "human", "lane": 2, "biosample_type": "immortalized cell line", "biosample_term_name": "K562", "biosample_term_id": "EFO:0002067"}]
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
  def test_antibody_characterizaton_two_methods(testapp, antibody_characterization):
      antibody_characterization['primary_characterization_method'] = 'immunoblot'
      antibody_characterization['secondary_characterization_method'] = 'dot blot assay'
      antibody_characterization['attachment'] = {'download': 'red-dot.png', 'href': RED_DOT}
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
  def test_antibody_status_wrangler(testapp, antibody_characterization):
      antibody_characterization['primary_characterization_method'] = 'immunoblot'
      antibody_characterization['status'] = 'compliant'
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
  
  def test_no_attachment(testapp, antibody_characterization):
      antibody_characterization['secondary_characterization_method'] = 'ChIP-seq comparison'
      testapp.post_json('/antibody_characterization', antibody_characterization, status=422)
  
subject: Add no attachment test to test_schema_antibody_characterization