'Closes the CHM archive.
This function will close the CHM file, if it is open. All variables
are also reset.'

def CloseCHM(self):

    if (self.filename is not None):
        chmlib.chm_close(self.file)
        self.file = None
        self.filename = ''
        self.title = ''
        self.home = '/'
        self.index = None
        self.topics = None
        self.encoding = None
