python中upper是做什么用的

str.upper()

#!/usr/bin/python
str = "this is string example....wow!!!"
print "str.upper() : ", str.upper()

str.upper() : THIS IS STRING EXAMPLE....WOW!!!

class A():
 def go(self):
  print ("go A go!")
 def stop(self):
  print ("stop A stop!")
 def pause(self):
  raise Exception("Not Implemented")
class B(A):
 def go(self):
  super(B, self).go()
  print ("go B go!")
class C(A):
 def go(self):
  super(C, self).go()
  print ("go C go!")
 def stop(self):
  super(C, self).stop()
  print ("stop C stop!")
class D(B,C):
 def go(self):
  super(D, self).go()
  print ("go D go!")
 def stop(self):
  super(D, self).stop()
  print ("stop D stop!")
 def pause(self):
  print ("wait D wait!")
class E(B,C):
 pass
a = A()
b = B()
c = C()
d = D()
e = E()
# 说明下列代码的输出结果
a.go()
print('--------')
b.go()
print('--------')
c.go()
print('--------')
d.go()
print('--------')
e.go()
print('--------')
a.stop()
print('--------')
b.stop()
print('--------')
c.stop()
print('--------')
d.stop()
print('--------')
e.stop()
print(D.mro())
a.pause()
b.pause()
c.pause()
d.pause()
e.pause()