"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-07 13:12:14.250917
"""

```python
from typing import List, Dict

class FactChecker:
    """
    A simple fact-checking class that evaluates statements based on a predefined set of facts.
    
    Attributes:
        knowledge_base: A dictionary containing facts where keys are statements and values are their truthiness (True or False).
    """
    def __init__(self, knowledge_base: Dict[str, bool]):
        self.knowledge_base = knowledge_base

    def check_fact(self, statement: str) -> bool:
        """
        Checks if a given statement is true based on the knowledge base.
        
        Args:
            statement: The statement to be checked.
            
        Returns:
            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, truthiness: bool) -> None:
        """
        Adds or updates a fact in the knowledge base.
        
        Args:
            statement: The new fact's statement.
            truthiness: The truth value of the new fact (True or False).
        """
        self.knowledge_base[statement] = truthiness

    def remove_fact(self, statement: str) -> None:
        """
        Removes a fact from the knowledge base if it exists.
        
        Args:
            statement: The statement to be removed.
        """
        if statement in self.knowledge_base:
            del self.knowledge_base[statement]

def example_usage():
    """Example usage of the FactChecker class."""
    # Initialize with some facts
    checker = FactChecker({
        "The Earth is round": True,
        "Paris is the capital of France": True,
        "Cats can't bark": True,
        "Water boils at 100 degrees Celsius": True
    })
    
    print(checker.check_fact("The Earth is round"))  # Output: True
    
    checker.add_fact("Dogs are birds", False)
    print(checker.check_fact("Dogs are birds"))  # Output: False
    
    checker.remove_fact("Paris is the capital of France")
    print(checker.check_fact("Paris is the capital of France"))  # Output: None, and implicitly False

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