def main():
print("Hi,")
print("This is the entrance of the demo package.")
print("")
print("Testing foo1: ")
foo1.speak()
print("")
print("Testing foo2: ")
foo2.speak()
print("")
print("Testing foo11: ")
foo11.speak()
def speak():
print("This is foo2 speaking, I'm from pakcage.subpackage2")
print("I invoked foo1: ")
foo1.speak()
