Let's say you have a custom exception `UnicornException` that you (or a library you use) might `raise`.

And you want to handle this exception globally with FastAPI.

You could add a custom exception handler with `@app.exception_handler()`:

{* ../../docs_src/handling_errors/tutorial003_py310.py hl[5:7,13:18,24] *}

Here, if you request `/unicorns/yolo`, the *path operation* will `raise` a `UnicornException`.

    # o schemaHtmlFileName: (NotRequired - Default 'schema-[project-name].html')
    #  The file name (not contain path) of SchemaHtml.
    #  Basically you don't need this.
    #  (For example, when you use Application Behavior, you need this)
    #
    #; schemaHtmlFileName = xxx.html
    # - - - - - - - - - -/

    # /- - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

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regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
with the License.  You may obtain a copy of the License at

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regarding copyright ownership.  The ASF licenses this file
to you under the Apache License, Version 2.0 (the
"License"); you may not use this file except in compliance
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