pragma solidity >=0.6.0; interface Token { function name() external view returns (string memory); function symbol() external view returns (string memory); function decimals() external view returns (uint8); function totalSupply() external view returns (uint); function balanceOf(address owner) external view returns (uint); function allowance(address owner, address spender) external view returns (uint); function approve(address spender, uint value) external returns (bool); function transfer(address to, uint value) external returns (bool); }