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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_all_glyphs_have_codepoints(ttFont):
 """Check all glyphs have codepoints assigned."""

  failed = False
  for subtable in ttFont['cmap'].tables:
    if subtable.isUnicode():
      for item in subtable.cmap.items():
        codepoint = item[0]
        if codepoint is None:
          failed = True
          yield FAIL, ("Glyph {} lacks a unicode"
                       " codepoint assignment").format(codepoint)
  if not failed:
    yield PASS, "All glyphs have a codepoint value assigned."