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## Etherscan

Configuration related to Etherscan, such as API keys. This configuration is used in various places by Forge.

The `[etherscan]` section is a mapping of keys to Etherscan configuration tables.

With Etherscan API V2, only Etherscan keys are valid, which can be used to access all similar explorers (e.g. BscScan / BaseScan / Polygonscan).

```toml
[etherscan]
mainnet = { key = "${ETHERSCAN_API_KEY}" }
mainnet2 = { key = "ABCDEFG", chain = "mainnet" }
optimism = { key = "1234567" }
unknown_chain = { key = "ABCDEFG", url = "<etherscan api url for this chain>" }
```