code: def normalize_input_path(x, data):
      
      if x is None:
          return None
      elif os.path.isabs(x):
          return os.path.normpath(x)
      else:
          for d in [data["dirs"].get("fastq"), data["dirs"].get("work")]:
              if d:
                  cur_x = os.path.normpath(os.path.join(d, x))
                  if os.path.exists(cur_x):
                      return cur_x
          raise IOError("Could not find validation file %s" % x)
docs: Normalize path for input files, handling relative paths.
      Looks for non-absolute paths in local and fastq directories