Python is there an ORM for SQL and NoSQL
No there is nothing like that.
An ORM or a RDBMS can rely on SQL as minimal standard for abstracting the underlaying database. Most ORM are build on top of the Python DB API (which is implemented more or less complete by all RDBMS Python bindings).
For NoSQL there is neither a standard query language nor a standard driver API.
So there is nothing like that that works for both worlds.
There have been approaches for defining a common query language for NoSQL language.
For example there is JsonIQ
http://www.jsoniq.org/
But there is not much that help you in reality.