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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 profile(self, username):
 """User profile page"""

        if not username and g.user:
            username = g.user.username

        payload = {
            'user': bootstrap_user_data(username, include_perms=True),
            'common': self.common_bootsrap_payload(),
        }

        return self.render_template(
            'superset/basic.html',
            title=_("%(user)s's profile", user=username),
            entry='profile',
            bootstrap_data=json.dumps(payload, default=utils.json_iso_dttm_ser),
        )