function get(arg, keys) {
  if (~networks.indexOf(arg)) {
    return arg;
  }
  if (keys) {
    if (!Array.isArray(keys)) {
      keys = [keys];
    }
    for (const index in networks) {
      if (keys.some(key => networks[index][key] === arg)) {
        return networks[index];
      }
    }
    return undefined;
  }
  if (networkMaps[arg] && networkMaps[arg].length >= 1) {
    return networkMaps[arg][0];
  } else {
    return networkMaps[arg];
  }
}
@function
@member Networks#get
Retrieves the network associated with a magic number or string.
@param {string|number|Network} arg
@param {string|Array} keys - if set, only check if the magic number associated with this name matches
@return Network