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+====== 4. Built-in Constants ======
+Created Sunday 02 December 2012
+
+A small number of constants live in the built-in namespace. They are:
+
+===== False =====
+The false value of the bool type.
+
+New in version 2.3.
+
+===== True =====
+The true value of the bool type.
+
+New in version 2.3.
+
+===== None =====
+The sole value of types.NoneType. None is frequently used to represent the absence of a value, as when default arguments are not passed to a function.
+
+Changed in version 2.4: Assignments to None are illegal and raise a SyntaxError.
+
+===== NotImplemented =====
+Special value which can be returned by the “rich comparison” special methods (__eq__(), __lt__(), and friends), to indicate that the comparison is not implemented with respect to the other type.
+
+===== Ellipsis =====
+Special value used in conjunction with extended slicing syntax.
+
+===== __debug__ =====
+This constant is true if Python was __not started with an -O option__. See also the assert statement.
+
+Note The names None and __debug__ cannot be reassigned (assignments to them, even as an attribute name, raise SyntaxError), so they can be considered “true” constants.
+Changed in version 2.7: Assignments to __debug__ as an attribute became illegal.
+
+===== 4.1. Constants added by the site module =====
+The site module (which is __imported automatically during startup__, except if the -S command-line option is given) adds several constants to the built-in namespace. They are useful for the interactive interpreter shell and should not be used in programs.
+
+===== quit([code=None]) =====
+
+===== exit([code=None]) =====
+Objects that when printed, print a message like “Use quit() or Ctrl-D (i.e. EOF) to exit”, and when called, raise SystemExit with the specified exit code.
+
+==== copyright ====
+
+==== license ====
+
+==== credits ====
+Objects that when printed, print a message like “Type license() to see the full license text”, and when called, display the corresponding text in a pager-like fashion (one screen at a time).
+
+»
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+© Copyright 1990-2012, Python Software Foundation. 
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+Last updated on Dec 02, 2012. Found a bug? 
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