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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 get_font(self, face, bold=False, italic=False):
 """Get a font described by face and size"""

        key = '%s-%s-%s' % (face, bold, italic)
        if key not in self._fonts:
            font = dict(face=face, bold=bold, italic=italic)
            self._fonts[key] = TextureFont(font, self._renderer)
        return self._fonts[key]