'Test that running a second file doesn\'t clobber the first, gh-3547'

def test_run_second(self):

    self.mktmp('avar    =    1\ndef    afunc():\n        return    avar\n')
    with tt.TempFileMixin() as empty:
        empty.mktmp('')
        _ip.magic(('run    %s' % self.fname))
        _ip.magic(('run    %s' % empty.fname))
        nt.assert_equal(_ip.user_ns['afunc'](), 1)
