python-3

7.

def func(name=None,**kwargs):
    print 'name:'+name
    for k ,w in kwargs.items():
        print '%s:%s'%(k,w)

func('Liyulong')
func('Liyulong',age=22)
func('Liyulong',age=22,weight=50)

6.
def func(*args):
    if type(args[2]) is str:
     print args[2]
    else:
     print 'None'

func(222,111,'xian','hahaah')
func(7,'name','fensi')
func(1,2,3,4)