object generator type mirrors JSON's objects. They generate key/value pairs whose keys are strings and values
are any sampled from any other generator type. With an
object, you can compose simpler generators into compound
generators that reflect complex data structures.
The keys of the JSON object to generate are inlined in the
object keys (e.g.
Values of objects can be made optional by specifying the
"optional": true attribute.
If a field should have the name
"type", this would clash with the predefined object attribute of the same name.
This can be worked around by changing the name to
"type_". The additional underscore will be removed in the