docs: def clean_query(query, replace=chr(26)):
          """
          Clean a query of invalid tokens.
          """
          accum = []
          any_invalid = False
          tokens = _quote_re.findall(query)
          for token in tokens:
              if token.startswith('"') and token.endswith('"'):
                  accum.append(token)
                  continue
              token_set = set(token)
              invalid_for_token = token_set & _invalid_ascii
              if invalid_for_token:
                  any_invalid = True
                  for c in invalid_for_token:
                      token = token.replace(c, replace)
              accum.append(token)
  
          if any_invalid:
              return ' '.join(accum)
          return query