def is_opentype_cff_font(filename):
if os.path.splitext(filename)[<NUM_LIT:1>].lower() == '<STR_LIT>':<EOL><INDENT>result = _is_opentype_cff_font_cache.get(filename)<EOL>if result is None:<EOL><INDENT>fd = open(filename, '<STR_LIT:rb>')<EOL>tag = fd.read(<NUM_LIT:4>)<EOL>fd.close()<EOL>result = (tag == '<STR_LIT>')<EOL>_is_opentype_cff_font_cache[filename] = result<EOL><DEDENT>return result<EOL><DEDENT>return False<EOL>
Returns True if the given font is a Postscript Compact Font Format
Font embedded in an OpenType wrapper.  Used by the PostScript and
PDF backends that can not subset these fonts.