444 No Response - Nginx 449 Retry With - Microsoft 450 Blocked by Windows Parental Controls - Microsoft 499 Client Closed Request - Nginx
506 Variant Also Negotiates - RFC 2295; experimental
Non-authentication POP3 protocol error (reply code “-ERR”, except authentication).
POP3 authentication error.
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.
Raises when there is an argument for a switch which takes no argument.
Raises when a switch with mandatory argument has no argument.
Raises when the given argument does not match required format.
Raises when the given argument word can’t be completed uniquely.
An abstract class for enumerating pseudo-prime numbers.
Concrete subclasses should override succ, next, rewind.