diff --git a/contracts/util/User.sol b/contracts/util/User.sol
new file mode 100644
index 0000000..2cb049a
--- /dev/null
+++ b/contracts/util/User.sol
@@ -0,0 +1,20 @@
+pragma solidity ^0.8.0;
+
+contract User {
+    function proxy(
+        address _target,
+        bytes memory _calldata
+    ) public returns (bool success, bytes memory returnData) {
+        (success, returnData) = _target.call(_calldata);
+    }
+
+    function proxy(
+        address _target,
+        bytes memory _calldata,
+        uint256 _value
+    ) public returns (bool success, bytes memory returnData) {
+        (success, returnData) = _target.call{value: _value}(_calldata);
+    }
+
+    receive() external payable {}
+}
\ No newline at end of file