escape_dictionary_key ( key )

Make sure the word class does not occur as a dictionary key. Prefix a key that is class with a backslash. Also prefix all keys that start with a backslash with another backslash.

instance_tree_to_basic_tree (
        itree,
        already_converted=None,
        allow_conversion=1,
        )

A tree of instances and basic Python types is converted to a tree of only basic types (numbers, strings, None, tuples, lists, dictionaries).

Instances are replaced by dictionaries which include a key indicating the instance class name. Instance should have an attribute called state_attributes set to a sequence of attribute names. These are the only attributes that will be included in the basic tree.

An instance cannot appear more than once in the input tree. A dictionary key cannot be an instance.

These two restrictions could be lifted in a more complex implementation that makes unique copies of the instances and returns an object that gives the tree of basic types with references to unique instances, and a list of the unique instances converted to basic types. This has not been done since it is not currently needed.

is_simple_sequence ( seq )

A simple sequence is of length <= 4 and contains only numbers or None.

unescape_dictionary_key ( key )

Remove leading backslash from string keys.

write_basic_tree (
        btree,
        file,
        indent='',
        start_of_line=1,
        )

Write a tree involving only basic Python types (numbers, strings, None, tuples, lists, dictionaries) to a file formatted for human readability.

write_sequence (
        btree,
        file,
        indent,
        sindent,
        )

Write sequence elements on separate lines.

write_simple_sequence (
        btree,
        file,
        indent,
        )

Write sequence elements on one line.