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# IERC1271

Interface for verifying contract-based account signatures

Interface that verifies provided signature for the data

*Developer note: Interface defined by EIP-1271*

## Functions

### isValidSignature

`function isValidSignature(bytes32 hash, bytes signature) external view returns (bytes4 magicValue)` view external

Returns whether the provided signature is valid for the provided data *Developer note: MUST return the bytes4 magic value 0x1626ba7e when function passes. MUST NOT modify state (using STATICCALL for solc < 0.5, view modifier for solc > 0.5). MUST allow external calls.*

| Name      | Type    | Description                                 |
| --------- | ------- | ------------------------------------------- |
| hash      | bytes32 | Hash of the data to be signed               |
| signature | bytes   | Signature byte array associated with \_data |

**Returns:**

| Name       | Type   | Description                       |
| ---------- | ------ | --------------------------------- |
| magicValue | bytes4 | The bytes4 magic value 0x1626ba7e |