@property
    def addr_spec(self):
        nameset = set(self.username)
        if len(nameset) > len(nameset-parser.DOT_ATOM_ENDS):
            lp = parser.quote_string(self.username)
        else:
            lp = self.username
        if self.domain:
            return lp + '@' + self.domain
        if not lp:
            return '<>'
        return lp
The addr_spec (username@domain) portion of the address, quoted
dataset/ETHPy150Open OpenCobolIDE/OpenCobolIDE/open_cobol_ide/extlibs/future/backports/email/headerregistry.py/Address.addr_spec