**FastAPI' nin** tamamı bu tür tip belirteçleri ile donatılmıştır ve birçok avantaj sağlamaktadır.

**FastAPI** kullanmayacak olsanız bile tür belirteçleri hakkında bilgi edinmenizde fayda var.

/// note | Not

Python uzmanıysanız ve tip belirteçleri ilgili her şeyi zaten biliyorsanız, sonraki bölüme geçin.

///

## Motivasyon

Basit bir örnek ile başlayalım:

{* ../../docs_src/python_types/tutorial001.py *}

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

	if u1.ID == 0 {
		t.Errorf("user's primary key should has value after create, got : %v", u1.ID)
	}

	if u1.CreatedAt.IsZero() {
		t.Errorf("user's created at should be not zero")
	}

	if u1.UpdatedAt.IsZero() {
		t.Errorf("user's updated at should be not zero")
	}

	var newUser User
	if err := DB.Where("id = ?", u1.ID).First(&newUser).Error; err != nil {
		t.Fatalf("errors happened when query: %v", err)
	} else {

			wantSelected: &inputSerialized[2],
			wantOk:       true,
		},
		{
			// inputSerialized[1] have older versions of the second in inputSerialized[2], but
			// since it is not strict, we should get it that one (with latest modtime)
			name:         "modtimemismatch,not strict",
			m:            metaCacheEntries{inputSerialized[1], inputSerialized[1], inputSerialized[2], inputSerialized[2]},

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,

/*
 * Copyright 2012-2025 CodeLibs Project and the Others.
 *
 * Licensed 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
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,