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what is None?

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None is used when there is no value. In Mathematics we use 0 to represent no quantity. In some languages or domains we use NULL, in forms we use N/A when the options do not apply. In Python we can use None.

I used assertIs and assertIsNot in the assertion_error project test_assertion_error_w_none in AssertionError, where I saw that

• True is NOT None and NOT equal to None

• False is NOT None and NOT equal to None

• None is None and equal to None

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the chapters

• None (the simplest object)
• AssertionError 3: use assertIsNotNone and assertIsNone

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what is next?

None (the simplest object)