Answers for "how to use python __init__.py"

__init__.py file in python

# __init__.py
# you can comment here about your package.
# you can also add external libraries to your package.
# for example:
import numpy
import pandas

# you can also add your package information in this file.
__version__ = '2.1.1'
__author__ = 'Depressed Dingo'

# __all__ make others able to access to this datas by importing our package.
__all__ = ['numpy', 'pandas', '__version__', '__author__']


# -----------------------------------------
# main.py
# example of using this.

from test_package import *
# or
from test_package import numpy

print(__auther__) # --> Depressed Dingo

init function in python

class Rectangle:
   def __init__(self, length, breadth, unit_cost=0):
       self.length = length
       self.breadth = breadth
       self.unit_cost = unit_cost
   def get_area(self):
       return self.length * self.breadth
   def calculate_cost(self):
       area = self.get_area()
       return area * self.unit_cost
# breadth = 120 units, length = 160 units, 1 sq unit cost = Rs 2000
r = Rectangle(160, 120, 2000)
print("Area of Rectangle: %s sq units" % (r.get_area()))

__init__ python

class A(object):
    def __init__(self):
        self.x = 'Hello'

    def method_a(self, foo):
        print self.x + ' ' + foo