How to use the pydantic.errors function in pydantic

def test_duplicates():
    with pytest.raises(errors.ConfigError) as exc_info:

        class Model(BaseModel):
            a: str
            b: str

            @validator('a')
            def duplicate_name(cls, v):
                return v

            @validator('b')  # noqa
            def duplicate_name(cls, v):  # noqa
                return v

    assert str(exc_info.value) == (
        'duplicate validator function '
        '"tests.test_validators.test_duplicates..Model.duplicate_name"; '

def validate_luhn_check_digit(cls, card_number: str) -> str:
        """
        Based on: https://en.wikipedia.org/wiki/Luhn_algorithm
        """
        sum_ = int(card_number[-1])
        length = len(card_number)
        parity = length % 2
        for i in range(length - 1):
            digit = int(card_number[i])
            if i % 2 == parity:
                digit *= 2
            sum_ += digit
        valid = sum_ % 10 == 0
        if not valid:
            raise errors.LuhnValidationError
        return card_number

def ip_v6_network_validator(v: Any) -> IPv6Network:
    """
    Assume IPv6Network initialised with a default ``strict`` argument

    See more:
    https://docs.python.org/library/ipaddress.html#ipaddress.IPv6Network
    """
    if isinstance(v, IPv6Network):
        return v

    try:
        return IPv6Network(v)
    except ValueError:
        raise errors.IPv6NetworkError()

def ip_v6_address_validator(v: Any) -> IPv6Address:
    if isinstance(v, IPv6Address):
        return v

    try:
        return IPv6Address(v)
    except ValueError:
        raise errors.IPv6AddressError()

def validate(cls, value: Decimal) -> Decimal:
        digit_tuple, exponent = value.as_tuple()[1:]
        if exponent in {'F', 'n', 'N'}:
            raise errors.DecimalIsNotFiniteError()

        if exponent >= 0:
            # A positive exponent adds that many trailing zeros.
            digits = len(digit_tuple) + exponent
            decimals = 0
        else:
            # If the absolute value of the negative exponent is larger than the
            # number of digits, then it's the same as the number of digits,
            # because it'll consume all of the digits in digit_tuple and then
            # add abs(exponent) - len(digit_tuple) leading zeros after the
            # decimal point.
            if abs(exponent) > len(digit_tuple):
                digits = decimals = abs(exponent)
            else:
                digits = len(digit_tuple)
                decimals = abs(exponent)

def validate(cls, value: Path) -> Path:
        if not value.is_dir():
            raise errors.PathNotADirectoryError(path=value)

        return value

def validate_json(v: Any, config: 'BaseConfig') -> Any:
    if v is None:
        # pass None through to other validators
        return v
    try:
        return config.json_loads(v)  # type: ignore
    except ValueError:
        raise errors.JsonError()
    except TypeError:
        raise errors.JsonTypeError()

def arbitrary_type_validator(v: Any) -> T:
        if isinstance(v, type_):
            return v
        raise errors.ArbitraryTypeError(expected_arbitrary_type=type_)

def validate(cls, value: Path) -> Path:
        if not value.is_file():
            raise errors.PathNotAFileError(path=value)

        return value

if isinstance(value, time):
        return value

    number = get_numeric(value, 'time')
    if number is not None:
        if number >= 86400:
            # doesn't make sense since the time time loop back around to 0
            raise errors.TimeError()
        return (datetime.min + timedelta(seconds=number)).time()

    if isinstance(value, bytes):
        value = value.decode()

    match = time_re.match(value)  # type: ignore
    if match is None:
        raise errors.TimeError()

    kw = match.groupdict()
    if kw['microsecond']:
        kw['microsecond'] = kw['microsecond'].ljust(6, '0')

    kw_ = {k: int(v) for k, v in kw.items() if v is not None}

    try:
        return time(**kw_)  # type: ignore
    except ValueError:
        raise errors.TimeError()