Python: JSON-friendly Database Library

At the risk of downvotes, here goes: I am looking for a JSON-friendly database management library in python. SQLite3 seems attractive at first glance because I would like to store the database locally (and a file is easily moved/manipulated). However, the SQL structure in general is poorly suited for my application. The data I am managing in Python is a dictionary with VERY DEEP nesting. So, to flatten this data to be useful in SQL is suboptimal. Since I intend to have multiple users reading and writing to the database simultaneously, I would prefer something that is ACID compliant. I am currently reading the "database JSON file" as a Python dictionary, making changes to data in the dictionary, and then again writing the entire dictionary to a JSON file. As the length of the JSON files increases, write times become excessive and the ability for users to simultaneously write to the file is lost. Are there any python libraries that support JSON database management for deep nests? If I could set a SQL table value to another table maybe we'd be in business but I haven't found anything indicating that is acceptable.