How to use the oauthlib.oauth1.rfc5849.Client function in oauthlib

def test_hmac_sha1(self):
        client = Client('client_key')
        # instance is using the correct signer method
        self.assertEqual(Client.SIGNATURE_METHODS[SIGNATURE_HMAC_SHA1],
                         client.SIGNATURE_METHODS[client.signature_method])

def test_rsa_no_key(self):
        client = Client('client_key', signature_method=SIGNATURE_RSA)
        self.assertRaises(ValueError, client.sign, 'http://example.com')

def test_register_method(self):
        Client.register_signature_method('PIZZA',
            lambda base_string, client: 'PIZZA')

        self.assertTrue('PIZZA' in Client.SIGNATURE_METHODS)

        client = Client('client_key', signature_method='PIZZA',
            timestamp='1234567890', nonce='abc')

        u, h, b = client.sign('http://example.com')

        self.assertEqual(h['Authorization'], (
            'OAuth oauth_nonce="abc", oauth_timestamp="1234567890", '
            'oauth_version="1.0", oauth_signature_method="PIZZA", '

def test_plaintext_method(self):
        client = Client('client_key',
                        signature_method=SIGNATURE_PLAINTEXT,
                        timestamp='1234567890',
                        nonce='abc',
                        client_secret='foo',
                        resource_owner_secret='bar')
        u, h, b = client.sign('http://example.com')
        correct = ('OAuth oauth_nonce="abc", oauth_timestamp="1234567890", '
                   'oauth_version="1.0", oauth_signature_method="PLAINTEXT", '
                   'oauth_consumer_key="client_key", '
                   'oauth_signature="foo%26bar"')
        self.assertEqual(h['Authorization'], correct)

def test_validate_signature(self):
        client = Client('foo', callback_uri='https://c.b/cb')
        _, headers, _ = client.sign(self.uri + '/extra')
        h, b, s = self.endpoint.create_request_token_response(
                self.uri, headers=headers)
        self.assertEqual(s, 401)

def test_register_method(self):
        Client.register_signature_method('PIZZA',
            lambda base_string, client: 'PIZZA')

        self.assertTrue('PIZZA' in Client.SIGNATURE_METHODS)

        client = Client('client_key', signature_method='PIZZA',
            timestamp='1234567890', nonce='abc')

        u, h, b = client.sign('http://example.com')

        self.assertEqual(h['Authorization'], (
            'OAuth oauth_nonce="abc", oauth_timestamp="1234567890", '
            'oauth_version="1.0", oauth_signature_method="PIZZA", '

def test_client_realm_sign_with_additional_realm(self):
        client = Client("client-key", realm="moo-realm")
        uri, header, body = client.sign("http://example-uri", realm="baa-realm")
        self.assertTrue(
            header["Authorization"].startswith('OAuth realm="baa-realm",'))
        # make sure sign() does not override the default realm
        self.assertEqual(client.realm, "moo-realm")

def test_hmac_sha256_method(self):
        client = Client('client_key', signature_method=SIGNATURE_HMAC_SHA256,
                        timestamp='1234567890', nonce='abc')
        u, h, b = client.sign('http://example.com')
        correct = ('OAuth oauth_nonce="abc", oauth_timestamp="1234567890", '
                   'oauth_version="1.0", oauth_signature_method="HMAC-SHA256", '
                   'oauth_consumer_key="client_key", '
                   'oauth_signature="JzgJWBxX664OiMW3WE4MEjtYwOjI%2FpaUWHqtdHe68Es%3D"')
        self.assertEqual(h['Authorization'], correct)

def test_invalid_signature_type(self):
        client = Client('client_key', signature_type='invalid')
        self.assertRaises(ValueError, client.sign, 'http://i.b/path')