We are currently solving the following issue within our repository. Here is the issue text:
--- BEGIN ISSUE ---
Add option to remove coupon code from basket
There isn't option to remove coupon code from basket. Should likely be done with basket command at basket view [this](https://github.com/shuup/shuup/blob/master/shuup/core/basket/commands.py#L177).

--- END ISSUE ---

Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
--- BEGIN FILES ---
Path: `shuup/front/basket/commands.py`
Content:
```
1 # -*- coding: utf-8 -*-
2 # This file is part of Shuup.
3 #
4 # Copyright (c) 2012-2018, Shuup Inc. All rights reserved.
5 #
6 # This source code is licensed under the OSL-3.0 license found in the
7 # LICENSE file in the root directory of this source tree.
8 from shuup.core.basket.commands import (  # noqa
9     handle_add, handle_add_campaign_code, handle_add_var, handle_clear,
10     handle_del, handle_update
11 )
12
```
--- END FILES ---

Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.

Here is an example:

```diff
diff --git a/examples/server_async.py b/examples/server_async.py
--- a/examples/server_async.py
+++ b/examples/server_async.py
@@ -313,4 +313,4 @@
 
 
 if __name__ == "__main__":
-    asyncio.run(run_async_server("."), debug=True)
+    asyncio.run(run_async_server(), debug=True)
diff --git a/examples/server_sync.py b/examples/server_sync.py
--- a/examples/server_sync.py
+++ b/examples/server_sync.py
@@ -313,5 +313,5 @@
 
 
 if __name__ == "__main__":
-    server = run_sync_server(".")
+    server = run_sync_server()
     server.shutdown()

```

diff --git a/shuup/front/basket/commands.py b/shuup/front/basket/commands.py
--- a/shuup/front/basket/commands.py
+++ b/shuup/front/basket/commands.py
@@ -7,5 +7,5 @@
 # LICENSE file in the root directory of this source tree.
 from shuup.core.basket.commands import (  # noqa
     handle_add, handle_add_campaign_code, handle_add_var, handle_clear,
-    handle_del, handle_update
+    handle_del, handle_remove_campaign_code, handle_update
 )

{"golden_diff": "diff --git a/shuup/front/basket/commands.py b/shuup/front/basket/commands.py\n--- a/shuup/front/basket/commands.py\n+++ b/shuup/front/basket/commands.py\n@@ -7,5 +7,5 @@\n # LICENSE file in the root directory of this source tree.\n from shuup.core.basket.commands import (  # noqa\n     handle_add, handle_add_campaign_code, handle_add_var, handle_clear,\n-    handle_del, handle_update\n+    handle_del, handle_remove_campaign_code, handle_update\n )\n", "issue": "Add option to remove coupon code from basket\nThere isn't option to remove coupon code from basket. Should likely be done with basket command at basket view [this](https://github.com/shuup/shuup/blob/master/shuup/core/basket/commands.py#L177).\n", "before_files": [{"content": "# -*- coding: utf-8 -*-\n# This file is part of Shuup.\n#\n# Copyright (c) 2012-2018, Shuup Inc. All rights reserved.\n#\n# This source code is licensed under the OSL-3.0 license found in the\n# LICENSE file in the root directory of this source tree.\nfrom shuup.core.basket.commands import (  # noqa\n    handle_add, handle_add_campaign_code, handle_add_var, handle_clear,\n    handle_del, handle_update\n)\n", "path": "shuup/front/basket/commands.py"}], "after_files": [{"content": "# -*- coding: utf-8 -*-\n# This file is part of Shuup.\n#\n# Copyright (c) 2012-2018, Shuup Inc. All rights reserved.\n#\n# This source code is licensed under the OSL-3.0 license found in the\n# LICENSE file in the root directory of this source tree.\nfrom shuup.core.basket.commands import (  # noqa\n    handle_add, handle_add_campaign_code, handle_add_var, handle_clear,\n    handle_del, handle_remove_campaign_code, handle_update\n)\n", "path": "shuup/front/basket/commands.py"}]}