"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-08 10:02:22.606968
"""

```python
from typing import List, Union


class FactChecker:
    """
    A simple fact-checking utility that evaluates statements based on predefined knowledge.
    """

    def __init__(self):
        self.knowledge_base = {
            "Earth is round": True,
            "Water freezes at 0 degrees Celsius": True,
            "Python was created in the late 1980s": True,
            "New York City is the capital of New York State": True,
            "Bananas are blue": False,
        }

    def check_fact(self, statement: str) -> Union[bool, None]:
        """
        Checks if a given statement is true or false based on the knowledge base.

        :param statement: The statement to be checked.
        :return: True if the statement is in the knowledge base and considered true,
                 False if it's considered false, otherwise None.
        """
        return self.knowledge_base.get(statement)


# Example usage
if __name__ == "__main__":
    fact_checker = FactChecker()
    
    print(fact_checker.check_fact("Earth is round"))  # Output: True
    print(fact_checker.check_fact("Bananas are blue"))  # Output: False
    print(fact_checker.check_fact("New York City is the capital of New York State"))  # Output: True
    print(fact_checker.check_fact("Python was created in the year 2023"))  # Output: None, not in knowledge base
```