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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def update(self):
 """ Update will try to update the target directory w.r.t source directory. Only files that are common to both directories will be updated, no new files or directories are created """


        self._copyfiles = False
        self._updatefiles = True
        self._purge = False
        self._creatdirs = False

        if self._verbose:
            self.log('Updating directory %s with %s\n' %
                     (self._dir2, self._dir1))
        self._dirdiffandupdate(self._dir1, self._dir2)