def merge_converters(*converters_to_merge):
    """
    Merges the given converter groups.
    
    Parameters
    ----------
    converters_to_merge : `dict` of (`str`, `FunctionType`)
        Audit log change converters.
    
    Returns
    -------
    merged_converters : `dict` of (`str`, `FunctionType`)
    """
    multi_type_converters = set()
    merged_converters = {}
    
    for converters in converters_to_merge:
        for key, converter in converters.items():
            if key in multi_type_converters:
                continue
            
            try:
                actual_converter = merged_converters[key]
            except KeyError:
                merged_converters[key] = converter
                continue
            
            if actual_converter is converter:
                continue
            
            del merged_converters[key]
            multi_type_converters.add(key)
            continue
    
    return merged_converters