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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_metadata_valid_filename_values(font, family_metadata):
 """METADATA.pb font.filename field contains font name in right format?"""

  expected = os.path.basename(font)
  failed = True
  for font_metadata in family_metadata.fonts:
    if font_metadata.filename == expected:
      failed = False
      yield PASS, ("METADATA.pb filename field contains"
                   " font name in right format.")
      break
  if failed:
    yield FAIL, ("None of the METADATA.pb filename fields match"
                f" correct font name format (\"{expected}\").")