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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 _theme_and_template_fp(self):
 """Return the full paths for theme and template in this page"""

        ptheme = self._config['theme'][0]
        if ptheme == "":
            ptheme = self.site.site_config['default_theme']
        pthemedir = os.path.join(self.site.dirs['themes'], ptheme)
        ptemplate = self._config['template'][0]
        if ptemplate == "":
            ptemplate = self.site.site_config['default_template']
        ptemplatefname = os.path.join(pthemedir, ptemplate)
        return (pthemedir, ptemplatefname)