, """mailhost!username@example.org (bangified host route used for uucp mailers)"""
, """"very.(),:;<>[]\".VERY.\"very@\\ \"very\".unusual"@strange.example.com (include non-letters character AND multiple at sign, the first one being double quoted)"""
, """user%example.com@example.org (% escaped mail route to user@example.com via example.org)"""
, """user-@example.org (local-part ending with non-alphanumeric character from the list of allowed printable characters)"""
, """postmaster@[123.123.123.123] (IP addresses are allowed instead of domains when in square brackets, but strongly discouraged)"""
, """postmaster@[IPv6:2001:0db8:85a3:0000:0000:8a2e:0370:7334] (IPv6 uses a different syntax)"""
, """_test@[IPv6:2001:0db8:85a3:0000:0000:8a2e:0370:7334] (begin with underscore different syntax)"""