static fromPSV(...args) {
        return io.fromPSV(...args).then((content) => new DataFrame(content));
    }
Create a DataFrame from a pipe separated values file. It returns a Promise.
@param {String | File} pathOrFile A path to the file (url or local) or a browser File object.
@param {Boolean} [header=true] A boolean indicating if the psv has a header or not.
@example
DataFrame.fromPSV('http://myurl/myfile.psv').then(df => df.show())
// For browser only
DataFrame.fromPSV(myFile).then(df => df.show())
// From node.js only
DataFrame.fromPSV('/my/absolue/path/myfile.psv').then(df => df.show())
DataFrame.fromPSV('/my/absolue/path/myfile.psv', true).then(df => df.show())