Test fails - division by zero

[tomron]

I run the test as described in the read me and I get the following error -

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ERROR: test_cronbach_alphas (test.StatsTest)
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Traceback (most recent call last):
  File "/Users/tomron/code/processRat/tci-stats/test/__init__.py", line 9, in test_cronbach_alphas
    self.assertEqual(cronbach_alpha(data), 1)
  File "/Users/tomron/code/processRat/tci-stats/tcistats/__init__.py", line 11, in cronbach_alpha
    (1 - variance_sum / total_var))
ZeroDivisionError: float division by zero
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It has to do with total_variance=0. So the solution might be -

if total_variance == 0:
    return 1
return ...