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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_attrs(self, username, attrs):
 """ set a list of attributes for a given user :param username: 'key' attribute of the user :type username: string :param attrs: attributes of the user :type attrs: dict ({<attr>: <value>}) """

        self._check_fix_users(username)
        for attr in attrs:
            self.users[username][attr] = attrs[attr]