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Mac gcloud install ImportError: No module named __future__

When installing gcloud for mac I get this error when I run the install.sh command according to docs here:
Traceback (most recent call last):
File "/path_to_unzipped_file/google-cloud-sdk/bin/bootstrapping/install.py", line 8, in <module>
from __future__ import absolute_import
I poked through and echoed out some stuff in the install shell script. It is setting the environment variables correctly (pointing to my default python installation, pointing to the correct location of the gcloud SDK).
If I just enter the python interpreter (using the same default python that the install script points to when running install.py) I can import the module just fine:
>>> from __future__ import absolute_import
>>>
Only other information worth noting is my default python setup is a virtual environment that I create from python 2.7.15 installed through brew. The virtual environment python bin is first in my PATH so python and python2 and python2.7 all invoke the correct binary. I've had no other issues installing packages on this setup so far.
If I echo the final line of the install.sh script that calls the install.py script it shows /path_to_virtualenv/bin/python -S /path_to_unzipped_file/google-cloud-sdk/bin/bootstrapping/install.py which is the correct python. Or am I missing something?

The script uses the -S command-line switch, which disables loading the site module on start-up.
However, it is a custom dedicated site module installed in a virtualenv that makes a virtualenv work. As such, the -S switch and virtualenvs are incompatible, with -S set fundamental imports such as from __future__ break down entirely.
You can either remove the -S switch from the install.bat command or use a wrapper script to strip it from the command line as you call your real virtualenv Python.

I had the error below when trying to run gcloud commands.
File "/usr/local/Caskroom/google-cloud-sdk/latest/google-cloud-sdk/lib/gcloud.py", line 20, in <module>
from __future__ import absolute_import
ImportError: No module named __future__
If you have your virtualenv sourced automatically you can specify the environment variable CLOUDSDK_PYTHON i.e. set -x CLOUDSDK_PYTHON /usr/bin/python to not use the virtualenv python.

In google-cloud-sdk/install.sh go to last line, remove variable $CLOUDSDK_PYTHON_ARGS as below.
"$CLOUDSDK_PYTHON" $CLOUDSDK_PYTHON_ARGS "${CLOUDSDK_ROOT_DIR}/bin/bootstrapping/install.py" "$#"
"$CLOUDSDK_PYTHON" "${CLOUDSDK_ROOT_DIR}/bin/bootstrapping/install.py" "$#"

Bash alias not working for Python script

Trying to set a Bash alias in order to run a Python script for Pygame.
I have the android.py acript in, /usr/local/bin/pgs4a-0.9.6/andoid.py.
Bash alias: alias pyg='python /usr/local/bin/pgs4a-0.9.6/android.py'
When I run python android.py when I am in the folder in executes just fine, but when I do it from any other folder or using the alias, I get the following error.
pyg
Traceback (most recent call last):
File "/usr/local/bin/pgs4a-0.9.6/android.py", line 11, in <module>
import interface
ImportError: No module named interface
Can anybody explain to me why this is?

Try this:
alias pyg='PYTHONPATH=/usr/local/bin/pgs4a-0.9.6 python /usr/local/bin/pgs4a-0.9.6/android.py'
That is, set your $PYTHONPATH environment variable to contain the directory with the code. You may need to adjust the PYTHONPATH to some other location, depending on where your interface package actually resides.

Anaconda doesn't find module cv2

I am using Anaconda on OS X Mavericks. When I try loading cv2 I get an import error (see below). Do you know how to fix this?
>>import cv2
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: dlopen(/usr/local/Cellar/opencv/2.4.8.2/lib/python2.7/site-packages/cv2.so,
2): Library not loaded: /usr/local/lib/libpng15.15.dylib
Referenced from: /usr/local/Cellar/opencv/2.4.8.2/lib/libopencv_highgui.2.4.dylib
Reason: image not found
I am not sure it's relevant, but in /usr/local/lib/ I have libpng16.16.dylib instead of libpng15.15.dylib.

This is the solution I found:
comment the PYTHONPATH environment in ~/.bash_profile, as suggested by #asmeurer
install opencv using https://binstar.org/jjhelmus/opencv

As suggested in this issue, I fixed this problem by simply executing
conda update hdf5

you could also just add it to your PYTHONPATH. here's how:
you should be able to get it to load through one of the other (non anaconda) python executables. mine were located at:
/usr/bin/python (default system python) and /usr/local/bin/python (brew)
call the python executable using the full path
once you successfully import cv2 run: cv2.__file__
this will give you the file's path which you can then take (full directory path not including filename) and add as the first argument to your PYTHONPATH defined in ~/.bash_profile
after changing the .bash_profile don't forget to run
source ~/.bash_profile to make the changes effective
fire up anaconda python and it should now find cv2

Why is PYTHONPATH being ignored?

I am setting PYTHONPATH to have a directory that includes a few .py files.
When I go into python and type "import file", the file cannot be find (it says "No module named wsj10").
If, however, I cd to the directory, and repeat the same process, then the file is found.
I am just not sure why PYTHONPATH is being ignored. I followed exact instructions from installation instructions of some software, so I know I am doing the right thing.
Any circumstances under which PYTHONPATH will be ignored, or import won't work?
Thanks.
Following a comment below, here is a transcript:
untar file1.tgz to file1/. file1.tgz contains a library/file called file1.py.
type in the shell:
export PYTHONPATH=`pwd`/file1/:./
echo $PYTHONPATH shows the variable was set.
run python and type "import file1"
I get the error:
Traceback (most recent call last):
File "<stdin>", line 1, in <module>
ImportError: No module named file1
If I do first "cd file1" and then to import file1 it identifies the file.

Any circumstances under which PYTHONPATH will be ignored, or import won't work?
Yes. I've set PYTHONPATH in my /home/me/.bashrc and all worked ok from terminal, but when Apache w/ mod_wsgi starts my python scripts, it acts under sysem or dedicated user, which knows nothing of my .bashrc.
For this particular situation, I just used apache config to set python path for apache (WSGIPythonPath option).

python gtk module opens display on import

I'm using the trick "python -c 'import myscript.py'" to perform a syntax check on a script which uses 'import gtk'.
I get the following error when performing the syntax check, which implies that the gtk module is executing a check for the X display, even though all that's being done at this point is to import the module.
Traceback (most recent call last):
File "<stdin>", line 15, in ?
File "myscript.py", line 21, in ?
import gtk
File "/usr/src/build/463937-i386/install/usr/lib/python2.3/site-packages/gtk-2.0/gtk/__init__.py", line 37, in ?
RuntimeError: could not open display
Is there a way to avoid this error when performing the syntax check?
Before you ask - I'm not able to set $DISPLAY before the syntax check is run. The check is being run on remote servers as part of a distributed build system. These servers do not have an X display available.

Importing modules in Python executes their code!
Well-behaved modules use the if __name__ == '__main__' trick to avoid side effects, but they can still fail - as happened to you.
[BTW, getting to ImportError means the whole file already has correct syntax.]
If you just want to check syntax, without running at all:
python -m py_compile my_script.py
will check one file (and produce a .pyc as a side effect).
python -m compileall ./
will check a whole dir recursively.
python -c 'compile(open("myscript.py").read(), "myscript.py", "exec")'
avoids creating a .pyc.
But note that merely checking the syntax in Python catches very few bugs! Importing does catch more, e.g. mispelled names. For even better checks, use tools like Pychecker / Pyflakes.

What exactly do you mean by 'syntax checking'?
Can't you use a tool like pylint to check for syntax errors?
Otherwise: a very ugly (but probably possible hack):
In your python script detect whether X is present.
If it's not => use GTK on DirectFramebuffer (no X needed then). You'll need to compile GTK on DirectFB (and/or pygtk) from source (some pointers here).

If the remote machine has vncserver installed, you can have a dummy server running and connect to that. Sample instructions:
remotemachine $ vncserver -depth 16 -geometry 800x600 :7
New 'X' desktop is remotemachine:7
Starting applications specified in /home/user/.vnc/xstartup
Log file is /home/user/.vnc/userve:7.log
remotemachine $ DISPLAY=:7 python -c 'import myscript.py'
…
remotemachine $ vncserver -kill :7
Killing Xtightvnc process ID 32058

In your myscript.py, you could do like this
if __name__=="__main__":
import gtk
That will not execute gtk's __init__.py when you do "python -c 'import myscript.py'"

If you are editing with IDLE, Alt+X will check syntax of current file without running it.