Python float string formatting

z='%.15f' % x
gives a 15 decimal precision float converted to a string.
It is possible to get more than 15 decimals using %.20f and
%.80g etc. But the decimals after 15th are not reliable.

****incrementing integers in python
i+=1
i*=5
i-=1
i/=2
all works. Note i**2 means i to the power 2
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Python have private class and module methods. To make a method private
to a class or a module use __before the name.
Ex;
def __privateMethod():
If you try to call this method outside the module or outside the class
declaration, python will generate a 'method not found' exception.
Python 万歳!!!