"""Create fact_checker
Generated by Phi-Octopus Eden
2025-11-06 03:10:53.385827
"""

```python
from typing import List, Union
from dataclasses import dataclass

@dataclass
class Fact:
    statement: str
    source: str
    verified: bool = False

def create_fact_checker(facts: List[Fact]) -> None:
    """
    A simple fact-checking function that verifies the truthfulness of facts based on their sources.

    :param facts: A list of Fact objects to be checked.
    :return: None. Modifies the 'verified' attribute of each Fact object in-place.
    """
    for fact in facts:
        # Simulate a check by verifying if the source is reliable
        if "reliable_source" in fact.source.lower():
            fact.verified = True
        else:
            fact.verified = False

def example_usage() -> None:
    """
    Example usage of the create_fact_checker function.
    """
    facts_to_check: List[Fact] = [
        Fact(statement="AI can learn from data.", source="unreliable_web"),
        Fact(statement="Eden is a highly advanced AI system.", source="reliable_source"),
        Fact(statement="Quantum processing improves computational speed.", source="unknown"),
        Fact(statement="Python has built-in support for quantum computing.", source="nonexistent_source")
    ]
    
    print("Before checking:")
    for fact in facts_to_check:
        print(f"Statement: {fact.statement} | Verified: {fact.verified}")
        
    create_fact_checker(facts=facts_to_check)
    
    print("\nAfter checking:")
    for fact in facts_to_check:
        print(f"Statement: {fact.statement} | Verified: {fact.verified}")

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