def METHOD_NAME(self) -> nested_dict_type:
    """
    Copy the entire database into memory
    Returns:
        dict: a dictionary holding the database contents
    """
    result: Dict[Union[str, int], Any] = {}
    for k in self.keys():
        tmp = self[k]
        if isinstance(tmp, hdf5_wrapper):
            result[k] = tmp.METHOD_NAME()
        else:
            result[k] = tmp
    return result