These methods are called to implement the augmented arithmetic
operations (\code{+=}, \code{-=}, \code{*=}, \code{/=}, \code{\%=},
\code{**=}, \code{<}\code{<=}, \code{>}\code{>=}, \code{\&=},
-\code{\^=}, \code{|=}). These methods should attempt to do the
+\code{\textasciicircum=}, \code{|=}). These methods should attempt to do the
operation in-place (modifying \var{self}) and return the result (which
could be, but does not have to be, \var{self}). If a specific method
is not defined, the augmented operation falls back to the normal