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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 set_pythonshell_font(self, font=None):
 """Python Shell only"""

        if font is None:
            font = QFont()
        for style in self.font_styles:
            style.apply_style(font=font,
                              is_default=style is self.default_style)
        self.ansi_handler.set_base_format(self.default_style.format)