Decorators ,Lambda Functions and Sequences of Python

#using Decorators   not understand reallyimport operatorclass Files:    def __init__(self,**kwargs):        self.properties =kwargs    def copy(self):        print "copying"    def move(self):        print "moving "    def remove(self):        print "deleting"    def get_properites(self):        return self.properties    def get_property(self,key):        return self.properties.get(key)    @property    def privacy(self):        return self.properties.get("privacy")    @privacy.setter    def privacy(self,c):        self.properties['privacy'] =c    @privacy.deleter    def privacy(self):        del self.properties['privacy']    #Lambda functions    def calcuate(self,x):        return x*2    def cal2(self,j):        t = lambda x: x * 2        return t(j)    # Multiple Arguments Using lambda    def MulArg(self,x,y):        t= lambda x,y:(x*y,x+y)        return t(x,y)    #Operators and KeyWords for sequences    def OKs(self):        t = tuple(range(29)) # tuple can not changed        l= list(range(23))    # list can change        print t        print l    # itemgetter Not easy really    def itemgetee(self):        getseconditem = operator.itemgetter(1)        ls =['a','b','c','d','e']        tu=('a','gg','d','c','f')        print (getseconditem(ls))        print (getseconditem(tu))        print (operator.itemgetter(1,3,5)('abcdefg'))def main():  # here not main(self)  ,will get error  TypeError: main() takes exactly 1 argument (0 given)    imageDoc = Files(privacy="secret",you="your")    print imageDoc.get_property("privacy")    print imageDoc.get_property("you")    D = Files()    D.privacy="dddddddddd"    print D.privacy # will get dddddddd    print imageDoc.calcuate(3)  # works    print D.calcuate(3)         # works    print D.cal2(3)    print D.MulArg(13,7)    print D.MulArg(13, 7)[0]    print D.MulArg(13, 7)[1]    print D.OKs()    D.itemgetee()main()