python-viem

python-viem is a lightweight Python utility that mirrors EVM chain metadata from the Viem TypeScript library. It enables standardized, cross-language access to chain definitions and supports fast O(1) lookups by chain ID, name, or network slug.

Installation

pip install python-viem

uv add python-viem # for uv users

Features

• Instant chain metadata lookup by:
  • chain_id (e.g., 8453 → "Base")
  • name (e.g., "Polygon" → 137)
  • network (e.g., "base-sepolia" → 84532)

Usage

from python_viem import get_chain_by_id, get_chain_by_name, get_chain_by_network
from python_viem.viem import CHAINS_BY_NETWORK, CHAINS_BY_NAME, CHAINS_BY_ID

print(get_chain_by_id(8453)["name"])        # Base
print(get_chain_by_name("polygon")["id"])   # 137
print(get_chain_by_network("base-sepolia")["id"])  # 43113

print(list(CHAINS_BY_NETWORK.keys())) # List of all network keys
print(list(CHAINS_BY_NAME.keys()))    # List of all chain names
print(list(CHAINS_BY_ID.keys()))      # List of all chain IDs

Functions

get_chain_by_id(chain_id: int) -> Optional[Dict[str, Any]]

get_chain_by_name(name: str) -> Optional[Dict[str, Any]]

get_chain_by_network(network: str) -> Optional[Dict[str, Any]]

All functions return the full chain metadata dictionary or None if not found.

Project Structure

python_viem/
├── __init__.py
├── viem.py
├── viem-chains.json

License

MIT