henry-hz

```graphviz test digraph G { graph [fontname = "Helvetica"]; node [fontname = "Helvetica" penwidth=0.2]; edge [fontname = "Helvetica" arrowsize="0.6" ]; splines="curved"

henry-hz

// SPDX-License-Identifier: MIT
// ^ recommended, included machine readable in bytecode metadata
// Software Package Data Exchange is an open standard

pragma solidity ^0.8.7;
// ^ floating pragma, min 0.8.7 max excluding 0.9.0
// same as complex pragma: pragma solidity >=0.8.7 <0.9.0;
// major.breakingchanges.bugfixes
// only makes the compiler check for compatibility and throws error if not matching!
// should only be floating during development, fixed everywhere during testing & deployment