425 Unordered Collection - existed only in draft
Non-authentication POP3 protocol error (reply code “-ERR”, except authentication).
POP3 authentication error.
The writer adapter class
Represents an SMTP authentication error.
Represents an SMTP command syntax error (error code 500)
Represents a fatal SMTP error (error code 5xx, except for 500)
Unexpected reply code returned from server.
Base class of exceptions from OptionParser.
Internal use. An implementation of Eratosthenes’ sieve