YAML is a human friendly data serialization standard for all programming
languages. It is commonly used for configuration files, logs, etc.

ruamel.yaml is a YAML 1.2 loader/dumper package for Python. It is a
derivative of Kirill Simonov’s PyYAML 3.11.

ruamel.yaml supports YAML 1.2 and has round-trip loaders and dumpers
that preserves, among others:

* comments
* block style and key ordering are kept, so you can diff the
    round-tripped source
* flow style sequences ( ‘a: b, c, d’)
* anchor names that are hand-crafted (i.e. not of the form``idNNN``)
* merges in dictionaries are preserved