"""Create fallback_executor
Generated by Phi-Octopus Eden
2025-11-08 14:24:35.472060
"""

```python
from typing import Callable, Any


class FallbackExecutor:
    """
    A class for executing a function with fallback mechanisms in case of errors.
    
    Attributes:
        primary: The main callable to be executed.
        secondary: An alternative callable to execute if the primary fails.
        on_error: A callback to handle exceptions from both calls.
    """
    
    def __init__(self, primary: Callable[..., Any], secondary: Callable[..., Any] = None, on_error: Callable[[Exception], None] = None):
        self.primary = primary
        self.secondary = secondary
        self.on_error = on_error
    
    def execute(self) -> Any:
        try:
            return self.primary()
        except Exception as e:
            if self.secondary:
                try:
                    result = self.secondary()
                    if callable(self.on_error):
                        self.on_error(e)
                    return result
                except Exception as se:
                    if callable(self.on_error):
                        self.on_error(se)
                    raise se from e
            else:
                if callable(self.on_error):
                    self.on_error(e)
                raise e


# Example usage
def main_function() -> str:
    """A function that may fail."""
    return "Main function executed successfully"

def secondary_function() -> str:
    """An alternative function to execute in case of failure."""
    return "Secondary function executed as fallback"

def handle_exception(e: Exception) -> None:
    """Callback for handling exceptions."""
    print(f"An error occurred: {e}")

# Create an instance of FallbackExecutor
executor = FallbackExecutor(main_function, secondary_function, handle_exception)

# Execute the main function with fallbacks and custom exception handler
try:
    result = executor.execute()
    print(result)
except Exception as e:
    print(f"Failed to execute: {e}")
```