"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-06 03:13:03.588725
"""

```python
from typing import List, Dict


class FactChecker:
    """
    A basic fact checker that evaluates statements against a predefined knowledge base.
    """

    def __init__(self, knowledge_base: Dict[str, bool]):
        """
        Initializes the fact checker with a given knowledge base.

        :param knowledge_base: Dictionary containing facts in the format {statement: is_true}
        """
        self.knowledge_base = knowledge_base

    def check_fact(self, statement: str) -> bool:
        """
        Checks if the given statement is true based on the knowledge base.

        :param statement: The statement to be checked.
        :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, truth_value: bool) -> None:
        """
        Adds a new fact or updates an existing one to the knowledge base.

        :param statement: The statement to be added or updated.
        :param truth_value: True if the statement is true, False otherwise.
        """
        self.knowledge_base[statement] = truth_value

    def get_knowledge(self) -> Dict[str, bool]:
        """
        Returns the current state of the knowledge base.

        :return: A dictionary containing all facts and their truth values.
        """
        return self.knowledge_base


def example_usage() -> None:
    """
    Demonstrates how to use the FactChecker class.
    """
    # Example knowledge base
    knowledge = {
        "Paris is the capital of France": True,
        "The Earth orbits the Sun": True,
        "2 + 2 equals 5": False
    }

    fact_checker = FactChecker(knowledge_base=knowledge)

    print(f"Is Paris the capital of France? {fact_checker.check_fact('Paris is the capital of France')}")  # Expected: True

    fact_checker.add_fact("The Moon orbits around Earth", True)
    print(f"Is the Moon orbiting Earth? {fact_checker.check_fact('The Moon orbits around Earth')}")  # Expected: True

    new_knowledge = fact_checker.get_knowledge()
    for statement, truth in new_knowledge.items():
        print(f"{statement}: {truth}")


if __name__ == "__main__":
    example_usage()
```

This code defines a `FactChecker` class that can be used to check the validity of statements against a predefined knowledge base. It includes methods to add and retrieve facts, as well as an example usage demonstrating how these methods work together.