my_range_yield

def my_range(*args):
    li = []
    if len(args)>3 or len(args)<1:
        raise ValueError
    if len(args)==1:
        k=1.0
        a=0.0
        while a<=args[0]:
            yield a
            a+=k
    elif len(args)==2:
        k=1.0
        a=args[0]
        while a<=args[1]:
            yield a
            a+=k
    elif len(args)==3:
        a = args[0]
        k = args[2]
        if args[2]==0.0: raise ValueError
        elif args[2]>0:
            while a <= args[1]:
                yield a
                a += k
        else:
            while a >= args[1]:
                yield a
                a += k
def main():
    try:
        for i in my_range(2):
            print(i)
        for i in my_range(2,3):
            print(i)
        for i in my_range(1.1,2.2,0.5):
            print(i)
        for i in my_range():
            print (i)

    except:
        print ("Zla wartosc")

if __name__=='__main__':
    main()
try:
    for i in my_range(2):
        print i
    for i in my_range(2,3):
        print i
    for i in my_range(1.1,2.2,0.5):
        print i
    for i in my_range():
        print i

except:
    print "Zla wartosc"