Примечание:Для этого артефакта существует новая версия:
2.0.15
Psych is a YAML parser and emitter
Psych is a YAML parser and emitter. Psych leverages libyaml[http://pyyaml.org/wiki/LibYAML]
for its YAML parsing and emitting capabilities. In addition to wrapping
libyaml, Psych also knows how to serialize and de-serialize most Ruby objects
to and from the YAML format.