{!../../../docs_src/sql_databases/sql_app/models.py!}
```

When accessing the attribute `items` in a `User`, as in `my_user.items`, it will have a list of `Item` SQLAlchemy models (from the `items` table) that have a foreign key pointing to this record in the `users` table.

When you access `my_user.items`, SQLAlchemy will actually go and fetch the items from the database in the `items` table and populate them here.

// (even though we now use errors exclusively, not warnings).

void myfunc(void) {}
int myvar = 5;
const char *mytext = "abcdef";
typedef int mytype;
enum {
	myenum = 1234,
};

#define myfunc_def myfunc
#define myvar_def myvar
#define mytext_def mytext
#define mytype_def mytype
#define myenum_def myenum
#define myint_def 12345
#define myfloat_def 1.5

def main(user_id: str):
    return user_id


# Pydantic 모델
class User(BaseModel):
    id: int
    name: str
    joined: date
```

위의 코드는 다음과 같이 사용될 수 있습니다:

```Python
my_user: User = User(id=3, name="John Doe", joined="2018-07-19")

second_user_data = {
    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```

def main(user_id: str):
    return user_id


# A Pydantic model
class User(BaseModel):
    id: int
    name: str
    joined: date
```

これは以下のように用いられます:

```Python
my_user: User = User(id=3, name="John Doe", joined="2018-07-19")

second_user_data = {
    "id": 4,
    "name": "Mary",
    "joined": "2018-11-30",
}

my_second_user: User = User(**second_user_data)
```

这将或多或少会成为一种“神奇”属性，其中表示该表与其他相关的表中的值。

```Python hl_lines="2  15  26"
{!../../../docs_src/sql_databases/sql_app/models.py!}
```

当访问 user 中的属性`items`时，如 中`my_user.items`，它将有一个`Item`SQLAlchemy 模型列表（来自`items`表），这些模型具有指向`users`表中此记录的外键。

当您访问`my_user.items`时，SQLAlchemy 实际上会从`items`表中的获取一批记录并在此处填充进去。

同样，当访问 Item中的属性`owner`时，它将包含表中的`User`SQLAlchemy 模型`users`。使用`owner_id`属性/列及其外键来了解要从`users`表中获取哪条记录。

## 创建 Pydantic 模型

)

import (
	mymath "math"
	"/foo/bar/long_package_path" // a comment
)

import (
	"package_a" // comment
	"package_b"
	my_better_c "package_c" // comment
	"package_d" // comment
	my_e "package_e" // comment

	"package_a"    // comment
	"package_bb"
	"package_ccc"  // comment
	"package_dddd" // comment
)

// print import paths as double-quoted strings

)

import (
	mymath "math"
	"/foo/bar/long_package_path"	// a comment
)

import (
	"package_a"	// comment
	"package_b"
	my_better_c "package_c"	// comment
	"package_d"		// comment
	my_e "package_e"	// comment

	"package_a"	// comment
	"package_bb"
	"package_ccc"	// comment
	"package_dddd"	// comment
)

// print import paths as double-quoted strings

// Name will return SystemVerification as name for SystemVerificationCheck
func (SystemVerificationCheck) Name() string {
	return "SystemVerification"
}

// Check runs all individual checks
func (sysver SystemVerificationCheck) Check() (warnings, errorList []error) {
	klog.V(1).Infoln("running all checks")