ValueError: could not convert string to float when running test_column_sum_min_max

[psathyan]

I am seeing this error when running s3tests_boto3

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ERROR: s3tests_boto3.functional.test_s3select.test_column_sum_min_max
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Traceback (most recent call last):
  File "/root/s3-tests/virtualenv/lib/python3.6/site-packages/nose/case.py", line 198, in runTest
    self.test(*self.arg)
  File "/root/s3-tests/s3tests_boto3/functional/test_s3select.py", line 233, in test_column_sum_min_max
    nose.tools.assert_equal( float(res_s3select), float(res_target))
ValueError: could not convert string to float: '\navg  function not found\n'

I am executing the tests from ceph_pacific branch.