Multiple contracts, with a contract that is not created

Is it possible to define variables representing addresses contracts with known interfaces which aren't created by the contract referring to them?

For example, could you write an act specification for this?
```solidity
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

interface IERC20 {
function transfer(address recipient, uint256 amount) external;
}

contract TransferOneToken {
IERC20 public token;

constructor(IERC20 _tokenAddress) {
require(address(_tokenAddress) != address(0), "Invalid token address");
token = _tokenAddress;
}

function transfer() public {
// Transfer 1 token from the contract to the sender
uint256 transferAmt = 1;
token.transfer(msg.sender, transferAmt);
}
}
```

Start by reviewing how Act specifications currently represent contracts and constructor-created addresses, then compare that model with the provided TransferOneToken example. Determine whether externally supplied IERC20 addresses are supported and identify the specification and verification behavior that would need to define completion.

Written by the indexing model from the issue text.