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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 _pys2fonts(self, line):
 """Updates custom font list"""


        font_name, ascii_font_data = self._split_tidy(line)
        font_data = base64.b64decode(ascii_font_data)

        # Get system font names
        system_fonts = font_manager.findSystemFonts()

        system_font_names = []
        for sys_font in system_fonts:
            system_font_names.append(
                font_manager.FontProperties(fname=sys_font).get_name()
            )

        # Use the system font if applicable
        if font_name not in system_font_names:
            self.code_array.custom_fonts[font_name] = font_data

        with open(self.temp_fontdir + os.sep + font_name, "wb") as font_file:
            font_file.write(font_data)

        with tempfile.NamedTemporaryFile() as fontsconf_tmpfile:
            fontsconf_tmpfile_name = fontsconf_tmpfile.name
            fontsconf_tmpfile.write(self.temp_fontdir)

        os.environ["FONTCONFIG_FILE"] = fontsconf_tmpfile_name