Finding type in python - TypeError 'unicode' object is not callable

I'm trying to make sure an object is a string type in Python (for google app engine). I'm doing this so that I can change it to a db.Text type if its more than 500 bytes. However, I keep getting the error: TypeError 'unicode' object is not callable

   开发者_运维知识库 if type(value) in types.StringTypes and len(value) > 499:
        value = db.Text(value)
    setattr(entity, key, value)

What should I use to test if the type of the object is a string?

I think you just need to remove the parentheses from types.StringTypes, since it is a tuple (and not callable, hence the error). Either that, or your code is actually using StringType, which means your code is making a new string instance instead of returning the str type. Either way, it looks like a typo. See the docs.

Why are you calling types.StringTypes ? It's a tuple:

>>> types.StringTypes
(<type 'str'>, <type 'unicode'>)

Use isinstance(value, types.StringTypes) and len(value) > 499

Greg Haskins is right

>>> types.StringTypes()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
TypeError: 'tuple' object is not callable
>>> types.StringTypes
(<type 'str'>, <type 'unicode'>)

Could you do

if type(variable_name) == type("")

Edit: Oops! I was looking at types.StringType, instead of types.StringTypes, so the test could be:

if type(value) in types.StringTypes and len(value) > 499:
    value = db.Text(value)

Where the main problem with the OP code was the presence of the parens at the end of types.StringTypes.

Original: A few problems here:

• If value holds a Unicode, testing it with type() will return types.UnicodeType
• The types.StringType is a constant, not a function, so drop the parentheses.
• Furthermore, types.StringType isn't iterable, so test against it with == or is.

Thus, your test could look something like:

if ((type(value) == types.StringType) or (type(value) == types.UnicodeType)) and len(value) > 499:
    value = db.Text(value)

I prefer isinstance(object_to_be_checked, str)