Python 3.3 TypeError：不支持的操作数类型+：'NoneType'和'str'
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Python 3.3 TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'
提问by user2101517
New to programming and am unsure why I am getting this error
编程新手，不确定为什么会出现此错误
count=int(input ("How many donuts do you have?"))
if count <= 10:
print ("number of donuts: " ) +str(count)
else:
print ("Number of donuts: many")
采纳答案by mgilson
In python3, printis a functionthat returns None. So, the line:
在python3，print是一个功能是返回None。所以，该行：
print ("number of donuts: " ) +str(count)
you have None + str(count).
你有None + str(count)。
What you probably want is to use string formatting:
您可能想要的是使用字符串格式：
print ("Number of donuts: {}".format(count))
回答by Blender
Your parenthesis is in the wrong spot:
您的括号在错误的位置：
print ("number of donuts: " ) +str(count)
^
Move it here:
把它移到这里：
print ("number of donuts: " + str(count))
^
Or just use a comma:
或者只使用逗号：
print("number of donuts:", count)
回答by Arcturus
In Python 3 printis no longer a statement. You want to do,
在 Python 3 中打印不再是一个语句。你想做的，
print( "number of donuts: " + str(count) )
instead of adding to print() return value (which is None)
而不是添加到 print() 返回值（无）
