"""Create fallback_executor
Generated by Phi-Octopus Eden
2025-11-08 10:28:01.606509
"""

```python
class FallbackExecutor:
    """
    A class for executing tasks with fallback options in case of errors.

    :param primary_executor: Callable object responsible for handling main execution.
    :param fallback_executors: List of callable objects to be used as fallbacks if the primary executor fails.
    """

    def __init__(self, primary_executor: callable, fallback_executors: list):
        self.primary_executor = primary_executor
        self.fallback_executors = fallback_executors

    def execute(self, *args, **kwargs) -> any:
        """
        Execute the task using the primary executor. If an error occurs, attempt to use a fallback.

        :param args: Positional arguments for the primary_executor.
        :param kwargs: Keyword arguments for the primary_executor and fallback_executors.
        :return: Result of the successful execution or None if all fallbacks fail.
        """
        try:
            return self.primary_executor(*args, **kwargs)
        except Exception as e:
            print(f"Primary executor failed with error: {e}")
            for fallback in self.fallback_executors:
                try:
                    result = fallback(*args, **kwargs)
                    print(f"Fallback executor {fallback.__name__} executed successfully.")
                    return result
                except Exception as fe:
                    print(f"Fallback executor {fallback.__name__} failed with error: {fe}")
            print("All fallback executors failed. Returning None.")
            return None


# Example usage

def primary_math_operation(a, b):
    """
    Primary mathematical operation that could fail under certain conditions.
    :param a: First operand.
    :param b: Second operand.
    :return: Result of the operation or None if an error occurs.
    """
    try:
        return int(a) + int(b)
    except ValueError:
        raise Exception("Invalid input types for addition")


def fallback_math_operation_1(a, b):
    """
    First fallback mathematical operation that returns 0 in case of failure.
    :param a: First operand.
    :param b: Second operand.
    :return: Result or 0 if an error occurs.
    """
    try:
        return int(a) + int(b)
    except ValueError:
        print("Failing with fallback_1 and returning 0")
        return 0


def fallback_math_operation_2(a, b):
    """
    Second fallback mathematical operation that returns -1 in case of failure.
    :param a: First operand.
    :param b: Second operand.
    :return: Result or -1 if an error occurs.
    """
    try:
        return int(a) + int(b)
    except ValueError:
        print("Failing with fallback_2 and returning -1")
        return -1


# Creating instances of the executors
primary_exec = primary_math_operation
fallback1 = fallback_math_operation_1
fallback2 = fallback_math_operation_2

# Using FallbackExecutor to handle the operations
executor = FallbackExecutor(primary_executor=primary_exec, fallback_executors=[fallback1, fallback2])

result = executor.execute('3', '4')
print(f"Result: {result}")  # Expected output: Result: 7

result = executor.execute('a', 'b')  # This should trigger a fallback
print(f"Result: {result}")  # Expected output might vary based on which fallback is used.
```

This code defines `FallbackExecutor` as required, including the example usage where it handles mathematical operations with primary and fallback functions.