docs: def process_file(self, path, dryrun):
          """
          Print files path.
          """
          # if dryrun just return files
          if dryrun:
              return path
  
          # scan file and match lines
          ret = []
          with open(path, "r") as infile:
              for line in infile:
                  if re.search(self.__exp, line):
                      ret.append(line)
  
          # if found matches return list of lines, else return None
          return ret if len(ret) > 0 else None