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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 claim_token(self, **params):
 """Claim current token by POSTing 'login' and 'password'. User's `Authorization` header value is returned in `WWW-Authenticate` header. """

        self._json_params.update(params)
        success, self.user = self.Model.authenticate_by_password(
            self._json_params)

        if success:
            headers = remember(self.request, self.user.username)
            return JHTTPOk('Token claimed', headers=headers)
        if self.user:
            raise JHTTPUnauthorized('Wrong login or password')
        else:
            raise JHTTPNotFound('User not found')