print("users' IDs: {}".format(user.uid for user in users)) fails.

[olemr]

Following the example in order to retrieve a uid other than your own, this command fails:

>>> print("users' IDs: {}".format(user.uid for user in users))
users' IDs: <generator object <genexpr> at 0x7f976aa8afa0>

I suspect this is because user names in my chat list contains national characters.
Trying just:

>>> print (users)
[<USERs listed up til ... >, 
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
UnicodeEncodeError: 'ascii' codec can't encode character u'\xf8' in position 13: ordinal not in range(128)

Running:

>>>import sys
>>>reload(sys)
>>>sys.setdefaultencoding('utf8')
>>> print (users)

luckily listed the user I wanted, and then hung my terminal window.

This command still don't work:

>>> print("users' IDs: {}".format(user.uid for user in users))
users' IDs: <generator object <genexpr> at 0x7f976aa8afa0>

[madsmtm]

This is really two issues:
The example is written wrongly, it prints <generator...> because we use a generator expression, not a list comprehension. The correct code is fixed in 08117e7:

print("users' IDs: {}".format([user.uid for user in users]))

The encoding errors are a duplicate of #302