code: def get_failed_instruments(self):
          
          bsc = api.get_tool("bika_setup_catalog")
          insts = bsc(portal_type="Instrument", is_active=True)
          for i in insts:
              i = i.getObject()
              instr = {
                  'uid': i.UID(),
                  'title': i.Title(),
              }
              if i.isValidationInProgress():
                  instr['link'] = '<a href="%s/validations">%s</a>' % (
                      i.absolute_url(), i.Title()
                  )
                  self.nr_failed += 1
                  self.failed['validation'].append(instr)
              elif i.isCalibrationInProgress():
                  instr['link'] = '<a href="%s/calibrations">%s</a>' % (
                      i.absolute_url(), i.Title()
                  )
                  self.nr_failed += 1
                  self.failed['calibration'].append(instr)
              elif i.isOutOfDate():
                  instr['link'] = '<a href="%s/certifications">%s</a>' % (
                      i.absolute_url(), i.Title()
                  )
                  self.nr_failed += 1
                  self.failed['out-of-date'].append(instr)
              elif not i.isQCValid():
                  instr['link'] = '<a href="%s/referenceanalyses">%s</a>' % (
                      i.absolute_url(), i.Title()
                  )
                  self.nr_failed += 1
                  self.failed['qc-fail'].append(instr)
              elif i.getDisposeUntilNextCalibrationTest():
                  instr['link'] = '<a href="%s/referenceanalyses">%s</a>' % (
                      i.absolute_url(), i.Title()
                  )
                  self.nr_failed += 1
                  self.failed['next-test'].append(instr)
docs: Find invalid instruments
  
          - instruments who have failed QC tests
          - instruments whose certificate is out of date
          - instruments which are disposed until next calibration test
  
          Return a dictionary with all info about expired/invalid instruments