Add Python cheatsheet.

content/languages/python.html

@@ -0,0 +1,38 @@
+--- 
+title: Floating-point cheat sheet for Python
+description: Tips for using floating-point and decimal numbers in Python
+--- 
+
+Floating-Point Types
+--------
+Almost all platforms map Python floats to [IEEE 754](/formats/fp/)
+double precision.
+
+        f = 0.1 
+
+Decimal Types
+-------------
+Python has an [arbitrary-precision](/formats/exact/) decimal type named <code>Decimal</code> in the <code>decimal</code> module, which
+also allows to choose the [rounding mode](/errors/rounding/).
+        a = Decimal('0.1')
+        b = Decimal('0.2')
+        c = a + b # returns a Decimal representing exactly 0.3
+
+
+How to Round
+------------
+To get a string:
+        "%.2f" % 1.2399 # returns "1.24"
+		"%.3f" % 1.2399 # returns "1.240"
+		"%.2f" % 1.2 # returns "1.20"
+To print to standard output:
+		print "%.2f" % 1.2399 # just use print and string formatting
+If you need a specific [rounding mode](/errors/rounding/) and other parameters can be defined in a Context object:
+        getcontext().prec = 7
+
+Resources 
+---------
+* [Floating Point Arithmetic: Issues and Limitations](http://docs.python.org/tutorial/floatingpoint.html)
+* [The decimal module](http://docs.python.org/library/decimal.html)
+    * [Context objects](http://docs.python.org/library/decimal.html#context-objects)
+* [String formatting in Python](http://docs.python.org/library/stdtypes.html#string-formatting-operations)