"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-06 02:53:16.642302
"""

```python
from typing import List
from functools import lru_cache


class FactChecker:
    """
    A simple fact-checking system that verifies if a given statement is supported by at least three sources.
    """

    def __init__(self):
        self.sources = []
    
    def add_source(self, source: str) -> None:
        """Add a new source of information."""
        self.sources.append(source)
    
    @lru_cache(maxsize=1024)
    def check_fact(self, statement: str) -> bool:
        """
        Check if the given statement is supported by at least three different sources.
        
        :param statement: The statement to be verified
        :return: True if the statement is supported by multiple sources, False otherwise
        """
        matching_sources = [source for source in self.sources if statement.lower() in source.lower()]
        return len(matching_sources) >= 3


def example_usage():
    fact_checker = FactChecker()
    fact_checker.add_source("Source A: The Eiffel Tower is located in Paris, France.")
    fact_checker.add_source("Source B: The Eiffel Tower is a famous landmark in Europe.")
    fact_checker.add_source("Source C: The Eiffel Tower was built by Gustave Eiffel for the 1889 World's Fair.")
    
    # Example statements
    statement1 = "The Eiffel Tower is located in Paris, France."
    statement2 = "Gustav Eiffel designed the Statue of Liberty."

    print(f"Checking '{statement1}': {fact_checker.check_fact(statement1)}")
    print(f"Checking '{statement2}': {fact_checker.check_fact(statement2)}")


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