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<TITLE>7.10 whichdb --
Guess which DBM module created a database</TITLE>
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Guess which DBM module created a database">
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<H1><A NAME="SECTION0091000000000000000000">
7.10 <tt class=module>whichdb</tt> --
         Guess which DBM module created a database</A>
</H1>

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<P>
The single function in this module attempts to guess which of the
several simple database modules available-<tt class=module><a href="module-dbm.html">dbm</a></tt>,
<tt class=module><a href="module-gdbm.html">gdbm</a></tt>, or <tt class=module><a href="module-dbhash.html">dbhash</a></tt>-should be used to open a
given file.

<P>
<dl><dt><b><a name="l2h-1407"><tt class=function>whichdb</tt></a></b> (<var>filename</var>)
<dd>
Returns one of the following values: <tt>None</tt> if the file can't be
opened because it's unreadable or doesn't exist; the empty string
(<tt>''</tt>) if the file's format can't be guessed; or a string
containing the required module name, such as <tt>'dbm'</tt> or
<tt>'gdbm'</tt>.
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