python constants code example

Example 1: delcare consatnt python

# You can't, just use uppercase to identify

Example 2: how to define a constant in python

You can't define a constant in Python unlike in other language, hence you can 
just make the variable all CAPS and add a comment using '#' saying that this is 
a constant variable.

Example 3: python cmath constants

cmath.e	Returns Euler's number (2.7182...)
cmath.inf	Returns a floating-point positive infinity value
cmath.infj	Returns a complex infinity value
cmath.nan	Returns floating-point NaN (Not a Number) value
cmath.nanj	Returns coplext NaN (Not a Number) value
cmath.pi	Returns PI (3.1415...)
cmath.tau	Returns tau (6.2831...)

Example 4: python constant

class CONST(object):
    __slots__ = ()
    FOO = 1234


CONST = CONST()

print(CONST.FOO)  # 1234

CONST.FOO = 4321  # AttributeError: 'CONST' object attribute 'FOO' is read-only
CONST.BAR = 5678  # AttributeError: 'CONST' object has no attribute 'BAR'