"""Create logic_validator
Generated by Phi-Octopus Eden
2025-11-08 06:24:58.724577
"""

```python
from typing import Callable, Any, TypeVar, Generic, cast

T = TypeVar('T')

class LogicValidator(Generic[T]):
    """
    A class to validate logic in functions or methods by wrapping them and checking preconditions and postconditions.

    Args:
        func: The function or method to be validated.
    """

    def __init__(self, func: Callable[..., T]) -> None:
        self._func = func

    def _validate_input(self, *args: Any) -> bool:
        """
        Check the preconditions before calling the function.

        Args:
            *args: The arguments passed to the function.

        Returns:
            True if input is valid; False otherwise.
        """
        # Example precondition check
        for arg in args:
            if not isinstance(arg, (int, float)):
                return False
        return True

    def _validate_output(self, result: Any) -> bool:
        """
        Check the postconditions after calling the function.

        Args:
            result: The result of the function call.

        Returns:
            True if output is valid; False otherwise.
        """
        # Example postcondition check
        return isinstance(result, (int, float))

    def __call__(self, *args: Any) -> T:
        """
        Call the wrapped function and validate its input and output.

        Args:
            *args: The arguments passed to the function.

        Returns:
            The result of the function call if valid; otherwise raises an exception.
        """
        if not self._validate_input(*args):
            raise ValueError("Input is invalid.")

        result = self._func(*args)

        if not self._validate_output(result):
            raise ValueError("Output is invalid.")

        return cast(T, result)


def add(a: int, b: int) -> int:
    """
    Add two numbers.

    Args:
        a: The first number.
        b: The second number.

    Returns:
        The sum of the two numbers.
    """
    return a + b


# Example usage
validator = LogicValidator(add)
try:
    print(validator(1, 2))  # This will work fine and output 3
except ValueError as e:
    print(f"Validation failed: {e}")

try:
    print(validator("1", "2"))  # This should fail validation
except ValueError as e:
    print(f"Validation failed: {e}")
```

This example demonstrates a `LogicValidator` class that wraps a function and validates its input and output. The `add` function is wrapped by the validator to ensure it only accepts integers and returns an integer, which are simple checks for this demonstration.