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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def com_google_fonts_check_old_ttfautohint(ttFont, ttfautohint_stats):
 """Font has old ttfautohint applied? 1. find which version was used, by inspecting name table entries 2. find which version of ttfautohint is installed """

  from fontbakery.utils import get_name_entry_strings

  def ttfautohint_version(values):
    import re
    for value in values:
      results = re.search(r'ttfautohint \(v(.*)\)', value)
      if results:
        return results.group(1)

  def installed_version_is_newer(installed, used):
    installed = list(map(int, installed.split(".")))
    used = list(map(int, used.split(".")))
    return installed > used

  if not ttfautohint_stats:
    yield ERROR, "ttfautohint is not available."
    return

  version_strings = get_name_entry_strings(ttFont, NameID.VERSION_STRING)
  ttfa_version = ttfautohint_version(version_strings)
  if len(version_strings) == 0:
    yield FAIL, Message("lacks-version-strings",
                        "This font file lacks mandatory "
                        "version strings in its name table.")
  elif ttfa_version is None:
    yield INFO, ("Could not detect which version of"
                 " ttfautohint was used in this font."
                 " It is typically specified as a comment"
                 " in the font version entries of the 'name' table."
                 " Such font version strings are currently:"
                 " {}").format(version_strings)
  else:
    installed_ttfa = ttfautohint_stats["version"]
    try:
      if installed_version_is_newer(installed_ttfa,
                                    ttfa_version):
        yield WARN, ("ttfautohint used in font = {};"
                     " installed = {}; Need to re-run"
                     " with the newer version!").format(ttfa_version,
                                                        installed_ttfa)
      else:
        yield PASS, (f"ttfautohint available in the system ({installed_ttfa}) is older"
                     f" than the one used in the font ({ttfa_version}).")
    except ValueError:
      yield FAIL, Message("parse-error",
                          ("Failed to parse ttfautohint version values:"
                           " installed = '{}';"
                           " used_in_font = '{}'").format(installed_ttfa,
                                                          ttfa_version))