'Test that extending an empty header with the contents of an existing
header can exactly duplicate that header, given strip=False and
end=True.'

def test_header_extend_exact(self):

    header = fits.getheader(self.data('test0.fits'))
    header2 = fits.Header()
    header2.extend(header, strip=False, end=True)
    assert (header == header2)
