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python 2.7.9/pycharm 4/windows7: 'file' object has no attribute 'readall'

I'm trying to write some VERY trivial thing in pycharm.
Problem:
sourceText = ""
with open("lang.txt", "rt") as sourceFile:
sourceText = sourceFile.readall()
print sourceText
when I enter "." after "sourceFile", I get popup that offers me "readall()" method. However, when I attempt to run the script, I get"
Traceback (most recent call last):
....languages/languages.py", line 4, in <module>
sourceText = sourceFile.readall()
AttributeError: 'file' object has no attribute 'readall'
The method is documented (I get popup, can get documentation for this method using Ctrl+Q) but it seems to be inaccessible.
I'm a bit confused.
I'd like to either:
Not receive any popups for inaccessible methods in pycharm.
Or figure out why I can't see it despite it being documented.
Advice?
I'm using windows 7 64 bit, and have two python 2.7.9 installations (32bit and 64bit), with 64bit being in path 1st. Pycharm is 4.0.5 community edition.

You are correct that readall is documented for the io module, but it's complaining about file, which does not have that method. You want the read() method to read all the data in the file in one large clump. You could also use readlines() which well return a list. I have the Pro 3.4 edition of PyCharm and it does not do this. I would report this as a bug to PyCharm.

Python 3: tokenize library changes

According to this: http://code.activestate.com/lists/python-list/413540/, tokenize.generate_tokens should be used and not tokenize.tokenize.
This works perfectly fine in Python 2.6. But it does not work anymore in Python 3:
>>> a = list(tokenize.generate_tokens(io.BytesIO("1\n".encode()).readline))
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "/usr/lib/python3.2/tokenize.py", line 439, in _tokenize
if line[pos] in '#\r\n': # skip comments or blank lines
However, also in Python 3, this works (and returns also the desired output):
a = list(tokenize.tokenize(io.BytesIO("1\n".encode()).readline))
According to the documentation, it seems like tokenize.tokenize is the new way to use this module: http://docs.python.org/py3k/library/tokenize.html. tokenize.generate_tokens isn't even documented anymore.
But, why is there still a generate_tokens function in this module, if it's not documented? I haven't found any PEP regarding this.
I'm trying to maintain a code base for Python 2.5-3.2, should I call generate_tokens for Python 2 and tokenize for Python 3? Aren't there any better ways?

generate_tokens seems to be really a strange thing in Python 3. It doesn't work like in Python 2. However, tokenize.tokenize behaves like the old Python 2 tokenize.generate_tokens. Therefore I wrote a little workaround:
import tokenize
if sys.hexversion >= 0x03000000d:
tokenize_func = tokenize.tokenize
else:
tokenize_func = tokenize.generate_tokens
Now I just use tokenize_func, which works without problems.

generate_tokens in python3 is undocumented but not uncommented. it's there for backward compatibility, so you can use it, but it's probably better to use the changed tokenize instead...

PyWin32 get network information/statistics

I am trying to get Network Statistics for my Windows 7 system using PyWin32.
The steps I followed:
1) Run COM MakePy utility and than select network list manager 1.0
type library under type library.
2) Above process generated this python file.
Now the problem I am facing is after the above two steps what should be my next step. I tried a couple of things like:
I copied the CLSID = IID('{DCB00000-570F-4A9B-8D69-199FDBA5723B}') line from the above generated python file and used it like
>>> import win32com
>>> obj = win32com.client.gencache.GetClassForCLSID("{DCB00000-570F-4A9B-8D69-199FDBA5723B}")
>>> obj.GetConnectivity()
Traceback (most recent call last):
File "<interactive input>", line 1, in <module>
TypeError: unbound method GetConnectivity() must be called with INetworkListManager instance as first argument (got nothing instead)
When I do obj.method() it show a list of all available method.
So, now I have no idea what to do or how to proceed and what is the general process of using Type library with pywin32.
The above task is just a part of learning process on how to use PyWin32,COM MakePy utility.
Is this even achievable using pywin32.?

You'll need to use win32com.client.Dispatch to actually create the object.
Also, the class you start with is the CoClass, in this case
class NetworkListManager(CoClassBaseClass): # A CoClass
is the one you want.
win32com.client.Dispatch('{DCB00C01-570F-4A9B-8D69-199FDBA5723B}')
works here.
Many of these Dispatch classes have a human readable dotted name as an alias, although
this particular one doesn't seem to.

Working around Python bug in different versions

I've come across a bug in Python (at least in 2.6.1) for the bytearray.fromhex function. This is what happens if you try the example from the docstring:
>>> bytearray.fromhex('B9 01EF')
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
TypeError: fromhex() argument 1 must be unicode, not str
This example works fine in Python 2.7, and I want to know the best way of coding around the problem. I don't want to always convert to unicode as it's a performance hit, and testing which Python version is being used feels wrong.
So is there a better way to code around this sort of problem so that it will work for all versions, preferably without slowing it down for the working Pythons?

For cases like this it's good to remember that a try block is very cheap if no exception is thrown. So I'd use:
try:
x = bytearray.fromhex(some_str)
except TypeError:
# Work-around for Python 2.6 bug
x = bytearray.fromhex(unicode(some_str))
This lets Python 2.6 work with a small performance hit, but 2.7 shouldn't suffer at all. It's certainly preferable to checking Python version explicitly!
The bug itself (and it certainly does seem to be one) is still present in Python 2.6.5, but I couldn't find any mention of it at bugs.python.org, so maybe it was fixed by accident in 2.7! It looks like a back-ported Python 3 feature that wasn't tested properly in 2.6.

You can also create your own function to do the work, conditionalized on what you need:
def my_fromhex(s):
return bytearray.fromhex(s)
try:
my_fromhex('hello')
except TypeError:
def my_fromhex(s):
return bytearray.fromhex(unicode(s))
and then use my_fromhex in your code. This way, the exception only happens once, and during your runtime, the correct function is used without excess unicode casting or exception machinery.

There is no spawnl function in python 2.6?

I just noticed that my old codes written in python 2.5 does not work now. I am in python 2.6 btw.
>>> os.spawnl(os.P_NOWAIT,"setup.exe")
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
File "c:\python26\lib\os.py", line 612, in spawnl
return spawnv(mode, file, args)
OSError: [Errno 22] Invalid argument
>>>
Any clue? or do you have any working sample of os.spawn* with NOWAIT option.
Update:
Even I put full path in os.spawnl(), Its still error.

thrope is right about subprocess being preferred. But the spawn* stuff is still there in 2.6. In fact, you can see that in your error message. Your first arg seems to be valid. I'd check the second arg, which is the path.

I got it work by adding DUMMY parameter finally, a bit funky though
This is not working
os.spawnl(os.P_NOWAIT,"Setup.exe")
This is also not working
os.spawnl(os.P_NOWAIT,"Setup.exe","")
But this is working
os.spawnl(os.P_NOWAIT,"Setup.exe","DUMMY")
Thanks all anyway.

I think its recommended to use the subprocess module these days rather than the os.spawn* functions. (I can't reproduce your problem, but I'm not on windows).

A Google search brings up this page about the same problem happening when there is a space in the Python installation path. I couldn't reproduce it here, but maybe it's the problem?
In any case, according to MS documentation this error value (EINVAL) should only be returned if the mode argument is invalid, which isn't the case here.

os.spawnl() requires full path to executable, while os.spawnlp() uses PATH environment variable to find it.
Update: Also it's common error to use unescaped backslashes in the path literal (try printing it to see whether it's interpreted right).