Document the dbhash module, and link to it from appropriate places.
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+\section{\module{dbhash} ---
+ DBM-style interface to the BSD database library}
+
+\declaremodule{standard}{dbhash}
+ \platform{Unix, Windows}
+\modulesynopsis{DBM-style interface to the BSD database library.}
+
+
+The \module{dbhash} module provides a function to open databases using
+the BSD \code{db} library. This module mirrors the interface of the
+other Python database modules that provide access to DBM-style
+databases. The \module{bsddb}\refbimodindex{bsddb} module is required
+to use \module{dbhash}.
+
+This module provides an exception and a function:
+
+
+\begin{excdesc}{error}
+ Exception raised on database errors other than
+ \exception{KeyError}. It is a synonym for \exception{bsddb.error}.
+\end{excdesc}
+
+\begin{funcdesc}{open}{path, flag\optional{, mode}}
+ Open a \code{db} database and return the database object. The
+ \var{path} argument is the name of the database file.
+
+ The \var{flag} argument can be
+ \code{'r'} (to open an existing database for reading only --- default),
+ \code{'w'} (to open an existing database for reading and writing),
+ \code{'c'} (which creates the database if it doesn't exist), or
+ \code{'n'} (which always creates a new empty database).
+ For platforms on which the BSD \code{db} library supports locking,
+ an \character{l} can be appended to indicate that locking should be
+ used.
+
+ The optional \var{mode} parameter is used to indicate the \UNIX{}
+ permission bits that should be set if a new database must be
+ created; this will be masked by the current umask value for the
+ process.
+\end{funcdesc}
+
+
+\begin{seealso}
+ \seemodule{anydbm}{Generic interface to \code{dbm}-style databases.}
+ \seemodule{whichdb}{Utility module used to determine the type of an
+ existing database.}
+\end{seealso}
+
+
+\subsection{Database Objects \label{dbhash-objects}}
+
+The database objects returned by \function{open()} provide the methods
+common to all the DBM-style databases. The following methods are
+available in addition to the standard methods.
+
+\begin{methoddesc}[dbhash]{first}{}
+ It's possible to loop over every key in the database using this method
+ and the \method{next()} method. The traversal is ordered by
+ the databases internal hash values, and won't be sorted by the key
+ values. This method returns the starting key.
+\end{methoddesc}
+
+\begin{methoddesc}[dbhash]{last}{}
+ Return the last key in a database traversal. This may be used to
+ begin a reverse-order traversal; see \method{previous()}.
+\end{methoddesc}
+
+\begin{methoddesc}[dbhash]{next}{key}
+ Returns the key that follows \var{key} in the traversal. The
+ following code prints every key in the database \code{db}, without
+ having to create a list in memory that contains them all:
+
+\begin{verbatim}
+k = db.first()
+while k != None:
+ print k
+ k = db.next(k)
+\end{verbatim}
+\end{methoddesc}
+
+\begin{methoddesc}[dbhash]{previous}{key}
+ Return the key that comes before \var{key} in a forward-traversal of
+ the database. In conjunction with \method{last()}, this may be used
+ to implement a reverse-order traversal.
+\end{methoddesc}
+
+\begin{methoddesc}[dbhash]{sync}{}
+ This method forces any unwritten data to be written to the disk.
+\end{methoddesc}