From http://docs.python.org/3.3/library/stdtypes.html#memoryview
len (view) is equal to the length of the list. If view.ndim = 0, the length is 1. If view.ndim = 1, the length is equal to the number of elements in the view. For large sizes, the length is equal to the length of the view of the nested view list. The items attribute will give you the number of bytes in one element.
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