id: no-numpy-nan-equality
valid:
  - |
    import numpy as np
    if np.isnan(x):
        pass
  - 'math.isnan(x)'
  - 'x is None'
  - 'x == 1'
invalid:
  - 'x == numpy.nan'
  - 'x != numpy.nan'
  - 'numpy.nan == x'
  - "x == float('nan')"
  - |
    import numpy as np
    if x is np.nan:
        pass
  - |
    import numpy as np
    if x == np.nan:
        pass