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Solve the following problem using Python, implementing the functions described below, one line at a time
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<USER_TASK:>
Description:
 def validate_password_reset(cls, code, new_password):

 """
 Validates an unhashed code against a hashed code.
 Once the code has been validated and confirmed
 new_password will replace the old users password
 """

        password_reset_model = \
            PasswordResetModel.where_code(code)
        if password_reset_model is None:
            return None
        jwt = JWT()
        if jwt.verify_token(password_reset_model.token):
            user = cls.where_id(jwt.data['data']['user_id'])
            if user is not None:
                user.set_password(new_password)
                PasswordResetModel.delete_where_user_id(user.id)
                return user
        password_reset_model.delete()  # delete expired/invalid token
        return None