For the last three years, Polkascan Foundation has been maintaining the Polkadot related Python libraries, such as [py-substrate-interface](https://github.com/polkascan/py-substrate-interface), [py-scale-codec](https://github.com/polkascan/py-scale-codec) and [several Python bindings](https://github.com/orgs/polkascan/repositories?q=&type=all&language=rust&sort=) for cryptographic RUST crates used by Substrate. These client libraries are essential for Python developers to interact with any Polkadot, Kusama or other Substrate based chain.

As of writing [265 Github repositories and 21 Python packages](https://github.com/polkascan/py-substrate-interface/network/dependents?package_id=UGFja2FnZS04OTc2NTczNTM%3D) are depending on our libraries.

With this treasury proposal, we are asking retroactive funding for our activities in the period April until September 2023.  This averages out to approximately 4135 euro per month spent on development and tech support activities.


## Overview of activities
* Implemented new [Polkascan Explorer](https://github.com/polkascan/py-substrate-interface-extension-polkascan) and [Subsquid](https://github.com/polkascan/py-substrate-interface-extension-subsquid) extensions to the py-substrate-interface [extension framework](https://polkascan.github.io/py-substrate-interface/extensions/). These utilize indexes from Polkascan Explorer and Subsquid API endpoints, so data can be queried and filtered that is not directly possible or very inefficient on the Substrate RPC.
* New [runtime interface](https://github.com/polkascan/py-substrate-interface/tree/az-runtime-interface): more intuitive approach to interface with the runtime functionality, this is planned to be available in the next major release.  
* Added [support for ink! v4](https://github.com/polkascan/py-substrate-interface/pull/347)
* Added [SCALE type definitions](https://github.com/polkascan/py-scale-codec/pull/112) for upcoming `MetadataV15` in Substrate. (Full support is still WIP)
* Added [multiple params as key support](https://github.com/polkascan/py-substrate-interface/pull/351) for `query_map()`
* Add support for runtime calls at other blocks than the most recent [#346](https://github.com/polkascan/py-substrate-interface/pull/346)
* Upgrade contract interface to support `WeightV2` [#337](https://github.com/polkascan/py-substrate-interface/pull/337)
* Updated [metadata docs](https://polkascan.github.io/py-substrate-metadata-docs/) for Polkadot & Kusama parachain and stand-alone runtimes
* Technical support on [Github](https://github.com/polkascan/py-substrate-interface/discussions) and in [#polkascan:matrix.org](https://matrix.to/#/#polkascan:matrix.org) and [substrate.stackexchange.com](https://substrate.stackexchange.com/questions/tagged/python) channels

For more details about deliverables see https://github.com/polkascan/py-substrate-interface/releases and https://github.com/polkascan/py-scale-codec/releases


## Activity report

Details about time spent and cost breakdown can be found in the [Q2 & Q3 activity report](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2023Q2-Q3.md).

## Previous activity reports

* [October 2020](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202010.md)
* [November 2020](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202011.md)
* [December 2020](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202012.md)
* [January 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202101.md)
* [February 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202102.md)
* [March 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202103.md)
* [April 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202104.md)
* [May 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202105.md)
* [June 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202106.md)
* [July 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202107.md)
* [August 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202108.md)
* [September 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-202109.md)
* [Quarter 4 2021](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2021Q4.md)
* [Quarter 1 2022](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2022Q1.md)
* [Quarter 2 2022](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2022Q2.md)
* [Quarter 3 2022](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2022Q3.md)
* [Quarter 4 2022](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2022Q4.md)
* [Quarter 1 2023](https://github.com/polkascan/social-contract/blob/master/polkadot/treasury-proposal-008-report-2023Q1.md)

- Polkascan Foundation has been maintaining important libraries for Python developers to interact with Polkadot and other Substrate based chains.
- They are asking for funding for their activities from April to September 2023.
- They have implemented new extensions and a more intuitive approach to interface with the runtime functionality.
- They have added support for ink! v4 and SCALE type definitions for upcoming MetadataV15 in Substrate.
- They have provided technical support on Github and other channels.

Requested: 0.64 undefined

#458 Maintenance & Support Python Libraries (April to September 2023)