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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 getHeader(self,exten=None):
 """ Return just the specified header extension fileutil is used instead of fits to account for non-FITS input images. openImage returns a fits object. """

        _image=fileutil.openImage(self._filename, clobber=False, memmap=False)
        _header=fileutil.getExtn(_image,extn=exten).header
        _image.close()
        del _image
        return _header