"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-08 02:48:43.067251
"""

```python
from typing import List, Dict, Any

class FactChecker:
    """
    A simple fact checking class that evaluates statements against a predefined knowledge base.
    """

    def __init__(self):
        self.knowledge_base: Dict[str, bool] = {
            "2 + 2": True,
            "Paris is the capital of France": True,
            "Water boils at 100 degrees Celsius": True,
            "The Earth revolves around the Sun": True,
            "Python was created by Guido van Rossum": True
        }

    def check_fact(self, statement: str) -> bool:
        """
        Checks if a given statement is true based on the predefined knowledge base.
        
        :param statement: The statement to be checked as a string.
        :return: True if the statement is in the knowledge base and marked as true, False otherwise.
        """
        return self.knowledge_base.get(statement, False)

    def add_fact(self, statement: str, is_true: bool) -> None:
        """
        Adds or updates a fact in the knowledge base.

        :param statement: The statement to be added or updated.
        :param is_true: A boolean indicating whether the given statement is true.
        """
        self.knowledge_base[statement] = is_true

def example_usage() -> None:
    checker = FactChecker()
    
    # Check existing facts
    print(checker.check_fact("2 + 2"))  # Output: True
    print(checker.check_fact("Paris is the capital of Germany"))  # Output: False
    
    # Add a new fact and check it
    checker.add_fact("The Moon orbits around Earth", True)
    print(checker.check_fact("The Moon orbits around Earth"))  # Output: True

# Run example usage if this script is executed directly
if __name__ == "__main__":
    example_usage()
```