Python我可以在生成器中添加元组吗？

Question

我想在前面添加('','Day').现在它为1到31的数字做了一个下拉菜单,我想在顶部选择'Day'.

DAY_CHOICES = (
    # I was hoping this would work but apparently generators don't work like this.
    # ('', 'Day'),
    (str(x), x) for x in range(1,32)
)

# I'll include this in the snippet in case there's some voodoo I can do here
from django import forms
class SignUpForm(forms.Form):
    day = forms.ChoiceField(choices=DAY_CHOICES)

Answer 1

你想要的itertools.chain().

for i in itertools.chain(('foo', 'bar'), xrange(1, 4)):
  print i