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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update_safety_check(first_dict: MutableMapping[K, V], second_dict: Mapping[K, V], compat: Callable[[V, V], bool] = equivalent) -> None: """Check the safety of updating one dictionary with another. Raises ValueError if dictionaries have non-compatible values for any key, where compatibility is determined by identity (they are the same item) or the `compat` function. Parameters first_dict, second_dict : dict-like All items in the second dictionary are checked against for conflicts against items in the first dictionary. compat : function, optional Binary operator to determine if two values are compatible. By default, checks for equivalence. """

    for k, v in second_dict.items():
        if k in first_dict and not compat(v, first_dict[k]):
            raise ValueError('unsafe to merge dictionaries without '
                             'overriding values; conflicting key %r' % k)