from typing import Any, Dict


def safe_dict_update(target: Dict[Any, Any], source: Dict[Any, Any]):
    """Updates a dict in-place with the values from another in a safe manner.

    If there are keys in both target and source that have values that are not equal an error will be raised.

    Args:
        target: The dict to update
        source: The dict to source new keys from
    """
    for key, value in source.items():
        if key in target and target[key] != value:
            raise Exception('Attempted to update dict with mismatched value.')
        target[key] = value