assertTrue(str.contains("count="), "Should contain count");
        assertTrue(str.contains("offset="), "Should contain offset");
    }

        assertTrue(infoString.contains("alloc=1000"), "toString should contain alloc");
        assertTrue(infoString.contains("free=500"), "toString should contain free");
        assertTrue(infoString.contains("sectPerAlloc=100"), "toString should contain sectPerAlloc");
        assertTrue(infoString.contains("bytesPerSect=512"), "toString should contain bytesPerSect");
    }

        assertTrue(resultString.contains("status=0"), "toString should contain the status.");
        assertTrue(resultString.contains("converter=13330"), "toString should contain the converter.");
        assertTrue(resultString.contains("entriesReturned=2"), "toString should contain the number of entries.");
        assertTrue(resultString.contains("totalAvailableEntries=5"), "toString should contain the total available entries.");
    }

        assertEquals(1, pairs.size(), "Should have 1 pair after removal");
        assertFalse(AvPairs.contains(pairs, AvPair.MsvAvFlags), "Should not contain MsvAvFlags");
        assertTrue(AvPairs.contains(pairs, AvPair.MsvAvTimestamp), "Should still contain MsvAvTimestamp");
    }

    /**
     * Test remove method with non-existing type
     */
    @Test

        String s = session.toString();
        assertTrue(s.contains("accountName="), "toString should contain accountName");
        assertTrue(s.contains("primaryDomain="), "toString should contain primaryDomain");
        assertTrue(s.contains("uid="), "toString should contain uid");
    }

        String ts = ex.toString();
        assertTrue(ts.contains("SmbUnsupportedOperationException"), "toString should contain class name");
        if (msg != null) {
            assertTrue(ts.contains(msg), "toString should contain provided message");
        } else {
            assertFalse(ts.contains(":"), "toString should not contain ':' when message is null");
        }
    }

    @Test

Let's first see how the normal API app would look like before adding the callback.

It will have a *path operation* that will receive an `Invoice` body, and a query parameter `callback_url` that will contain the URL for the callback.

This part is pretty normal, most of the code is probably already familiar to you:

{* ../../docs_src/openapi_callbacks/tutorial001.py hl[9:13,36:53] *}

/// tip

        assertTrue("Result should contain sorted tags", result.contains("aaammmzzz"));
        assertTrue("Result should contain sorted roles", result.contains("role1role2role3"));
        assertTrue("Result should contain sorted fields", result.contains("field1field2field3"));
        assertTrue("Result should contain sorted excludes", result.contains("exclude1exclude2exclude3"));
    }

        // toString uses Hexdump.toHexString(informationLevel, 3)
        assertTrue(str.contains(Hexdump.toHexString(level, 3)), "toString should contain hex level");
        assertTrue(str.contains("Trans2QueryFSInformation["), "should start with class name");
        assertTrue(str.contains(",informationLevel=0x"), "should contain level field marker");
    }

        assertTrue(result.startsWith("SmbComNegotiate["), "String should start with SmbComNegotiate[");
        assertTrue(result.contains("wordCount=0"), "String should contain wordCount=0");
        assertTrue(result.contains("dialects=NT LM 0.12]"), "String should contain dialects=NT LM 0.12]");
    }