code: function postcss(...plugins) {
    if (plugins.length === 1 && Array.isArray(plugins[0])) {
      plugins = plugins[0];
    }
    return new Processor(plugins);
  }
docs: Create a new {@link Processor} instance that will apply `plugins`
  as CSS processors.
  
  @param {Array.<Plugin|pluginFunction>|Processor} plugins - PostCSS
  plugins. See {@link Processor#use} for plugin format.
  
  @return {Processor} Processor to process multiple CSS
  
  @example
  import postcss from 'postcss';
  
  postcss(plugins).process(css, { from, to }).then(result => {
  console.log(result.css);
  });
  
  @namespace postcss