# ethers-core Ethereum data types, cryptography and utilities. > **Warning** > > This library is in the process of being deprecated. See [#2667](https://github.com/gakonst/ethers-rs/issues/2667) for more information. It is recommended to use the `utils`, `types` and `abi` re-exports instead of the `core` module to simplify your imports. This library provides type definitions for Ethereum's main datatypes along with other utilities for interacting with the Ethereum ecosystem For more information, please refer to the [book](https://gakonst.com/ethers-rs). ## Feature flags - `eip712`: Does nothing. ## ABI This crate re-exports the [`ethabi`](https://docs.rs/ethabi) crate's functions under the `abi` module, as well as the [`secp256k1`](https://docs.rs/libsecp256k1) and [`rand`](https://docs.rs/rand) crates for convenience. ## Utilities The crate provides utilities for launching local Ethereum testnets by using `ganache-cli` via the `GanacheBuilder` struct. ## Examples Calculate the UniswapV2 pair address for two ERC20 tokens: ```rust # use ethers_core::abi::{self, Token}; # use ethers_core::types::{Address, H256}; # use ethers_core::utils; let factory: Address = "0x5C69bEe701ef814a2B6a3EDD4B1652CB9cc5aA6f".parse()?; let token_a: Address = "0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48".parse()?; let token_b: Address = "0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2".parse()?; let encoded = abi::encode_packed(&[Token::Address(token_a), Token::Address(token_b)])?; let salt = utils::keccak256(encoded); let init_code_hash: H256 = "0x96e8ac4277198ff8b6f785478aa9a39f403cb768dd02cbee326c3e7da348845f".parse()?; let pair = utils::get_create2_address_from_hash(factory, salt, init_code_hash); let weth_usdc = "0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc".parse()?; assert_eq!(pair, weth_usdc); # Ok::<(), Box>(()) ```