ValueError: not enough values to unpack (expected 2, got 1)

>> x,y = input("Enter a two value:").split()
Enter a two value:10
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ValueError: not enough values to unpack (expected 2, got 1)

原因是：输入的值不是期望的值，输入的俩个值的不能换行

>>> x,y = input("Enter a two value:").split()
Enter a two value:10 20