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python - How to delete [NaN] from a list of lists?

I have the following

a = [[u'63764'], [u'63764'], [u'63764'], [u'70272'], [u'98362'], [u'NaN'], [u'NaN']]

How do I delete all those [NaN]s to get:

a = [[u'63764'], [u'63764'], [u'63764'], [u'70272'], [u'98362']]

Thank You

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Use math.isnan to check whether the number is NaN:

>>> NaN = float('nan')
>>> import math
>>> math.isnan(1)
False
>>> math.isnan(NaN)
True

with list comprehension:

>>> [xs for xs in a if not any(math.isnan(x) for x in xs)]
[[1], [1], [2], [2], [2], [3], [3]]

UPDATE according to the question edit:

>>> a = [[u'63764'], [u'63764'], [u'63764'], [u'70272'], [u'98362'], [u'NaN'], [u'NaN']]
>>> [x for x in a if x != [u'NaN']]
[[u'63764'], [u'63764'], [u'63764'], [u'70272'], [u'98362']]

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