example_of_simple_default_data_member.py

#!/usr/bin/env python3
def load_on_default( obj, pargs ):
    for k, v in pargs.items():
      if( hasattr( obj, k ) ):
        setattr(obj, k, v )
      else:
        print( "WARNING: the key \"{}\" is wrong.".format(k) )

class MyClass:
    def __init__(self,**pargs):
        self.a = 1
        self.b = 2
        load_on_default(self,pargs)

myobj = MyClass(a=2,b=3)
print( 'a={}\tb={}'.format(myobj.a,myobj.b) )

myobj = MyClass(a=4,d=5)
print( 'a={}\tb={}'.format(myobj.a,myobj.b) )

results.txt

a=2    	b=3
WARNING: the key "d" is wrong.
a=4    	b=2