def test_openapi_schema():
    with client:
        response = client.get("/openapi.json")
        assert response.json() == {
            "openapi": "3.1.0",
            "info": {"title": "FastAPI", "version": "0.1.0"},
            "paths": {
                "/invoices/": {
                    "post": {
                        "summary": "Create Invoice",

Prefer either:
  * Provide only non-nullable version and move the `null` check to the call site (if the number of nullable callsites is low).
  * Provide two overloads with a different names (as Java doesn't support overloading on nullability). See 

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 *
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/*
 * Copyright 2020 the original author or authors.
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 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
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 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

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