(nested_dict)
return {k: i for (i, k) in enumerate(combined_keys)}
Combine the outer and inner keys of nested dictionaries into a single
    ordering.
Combine the outer and inner keys of nested dictionaries into a single
    ordering.
Combine the outer and inner keys of nested dictionaries into a single ordering .
def flattened_nested_key_indices(nested_dict):
    """
    Combine the outer and inner keys of nested dictionaries into a single
    ordering.
    """
    outer_keys, inner_keys = collect_nested_keys(nested_dict)
    combined_keys = list(sorted(set(outer_keys + inner_keys)))
    return {k: i for (i, k) in enumerate(combined_keys)}
def flattened_nested_key_indices ( nested_dict ) : outer_keys , inner_keys = collect_nested_keys ( nested_dict ) combined_keys = list ( sorted ( set ( outer_keys + inner_keys ) ) ) return { k : i for ( i , k ) in enumerate ( combined_keys ) }