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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_full_name_values(style, font_metadata, font_familynames, typographic_familynames):
 """METADATA.pb font.full_name field contains font name in right format?"""

  from fontbakery.constants import RIBBI_STYLE_NAMES
  if style in RIBBI_STYLE_NAMES:
    familynames = font_familynames
    if familynames == []:
      yield SKIP, "No FONT_FAMILYNAME"
  else:
    familynames = typographic_familynames
    if familynames == []:
      yield SKIP, "No TYPOGRAPHIC_FAMILYNAME"

  for font_familyname in familynames:
    if font_familyname in font_metadata.full_name:
      yield PASS, ("METADATA.pb font.full_name field contains"
                   " font name in right format."
                   " ('{}' in '{}')").format(font_familyname,
                                             font_metadata.full_name)
    else:
      yield FAIL, ("METADATA.pb font.full_name field (\"{}\")"
                   " does not match correct font name format (\"{}\")."
                   "").format(font_metadata.full_name,
                              font_familyname)