Where can I find the API for determining the main belts of the Russian Post?

Question

API

Colleagues, hello!
I'm trying to solve a problem for calculating the optimal delivery options for an online store. Delivery services have certain APIs that allow you to calculate shipping costs automatically. We did not find this at the Russian Post, but it is impossible to refuse mail.
There is already a system that calculates the cost of delivery with all the costs of delivery services, so there is no need for a service that makes a full calculation of the cost of delivery of the Russian Post.
At the Russian Post, the tariffing for sending goes according to the main belts, and if you know this very main belt at the address of the recipient, then you can quickly calculate the cost of delivery.
Hence the question: where can I find a service that can receive a post office index as an input, and can give a trunk belt number as an output? Preferably all this in JSON. The service may even be paid if there are no other options.
PS The option to store the "index - main" belt sets has been considered, and left as a last resort. The option is not very complicated, since the main belt will depend only on the first three digits of the index. But someone has to be aware of possible changes in indexes and backbone belts, and we don't have people who can constantly monitor these data.

Answer 1

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