encode method
Implementation
String encode() {
final pName = personalName;
if (pName == null) {
return email;
}
var buffer = StringBuffer()
..write('"')
..write(MailCodec.quotedPrintable.encodeHeader(pName, fromStart: true))
..write('" <')
..write(email)
..write('>');
return buffer.toString();
}