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Problem with importing rospy and roslib libraries

I am new to ROS and python. This question could be silly but spent almost 5 hours on this. I am using PyCharm (Latest version) with Python 2.7.15 64 bit (Also tried with 3.x). I need to import a few libraries as below:
import roslib;
roslib.load_manifest('smach_tutorials')
import rospy
import smach
import smach_ros
However, PyCharm fails to identify roslib, rospy, smach and smach_ros (could not find in the interpreter also to import). The above libraries are example given in the official site:
http://wiki.ros.org/smach/Tutorials/Simple%20State%20Machine
OS: Windows 7 (64 bit)
ROS not installed: ("SMACH is a ROS-independent Python library to build hierarchical state machines" - from the official site)
Error Traceback:
Traceback (most recent call last):
File "C:/Users/****/Desktop/Python/TestCharm.py", line 3, in <module>
import roslib;
ModuleNotFoundError: No module named 'roslib'

If you are using the catkin version of ROS (Groovy and later), it does not use the manifest file but uses the package.xml file instead.
So your code will be:
import rospy
import smach
Apparently, your code is ready for ROS Fuerte or earlier version.
With supposing that Smach is ROS-independent, you need only to the import smach

Thanks for all the support. I found out it is not possible for my perticular case to use SMACH because it has dependency on catkin. I am using Windows 7 and should be upgraded to windows 10 or use Ununtu Linux.

Import not working when file is located in same directory and calling script

I'm not sure if the title of this question is correct, mods please feel free to change it.
I'm working through cs231n Convolutional Neural Networks for Visual Recognition course online and I've hit a weird error. This is my first attempt at any real Python programming so it could be a simple error, or something more complicated.
I'm using Python 2.7, Anaconda, and Windows 7.
When trying to run a script I get the following error;
NameError: global name 'im2col_cython' is not defined
My understanding so far is that this occurs because this fails (and calls the exception);
try:
from cs231n.im2col_cython import col2im_cython, im2col_cython
from cs231n.im2col_cython import col2im_6d_cython
except ImportError:
print 'run the following from the cs231n directory and try again:'
print 'python setup.py build_ext --inplace'
print 'You may also need to restart your iPython kernel'
I've tried to figure out why this may be the case. First off I have to run setup.py to turn im2col_cython.pyx into other files. This seems to run but does at one point have the warning;
warning: extension name 'im2col_cython' does not match fully qualified name 'cs231n.im2col_cython' of 'im2col_cython.pyx'
My figuring here is that it's an issue to do with the fact that the folder tree I have looks like this;
Assignment 2
->cs231n
Inside cs231n is where the setup.py and im2col_cython.pyx files are located. I've installed cython, and I have vc for python2.7 installed. When I run setup.py is creates 2 new files;
im2col_cython.c
im2col_cython.pyd
But I have no idea if that's what it's meant to do or anything. I'm in way over my head with this (0 Python knowledge), but I'm keen to learn!
EDIT 1
The script that imports im2col_cython is here
The im2col_cython file is here
EDIT 2
When including the following in the exception clause;
import traceback; traceback.print_exc()
I get this output;
Traceback (most recent call last):
File "fast_layers.py", line 3, in <module>
from cs231n.im2col_cython import col2im_cython, im2col_cython
ImportError: No module named cs231n.im2col_cython

Add this in the file fast_layer.py before import cs231n.im2col_cython:
import pyximport
pyximport.install()
The problem you mentioned should be fixed.

Python import Error: from .decoder import JSONDecoder: invalid syntax

I have a python module (getActiveLocation.py). It basically makes a http POST call, processes its response and returns it.
It makes use of json module. I am running python 2.6 on RedHat Linux. This module works fine when it is run standalone.
When the module getActiveLocation.py is run standalone, sys.path is
['/current_directory/','/usr/lib64/python26.zip','/usr/lib64/python2.6','/usr/lib64/python2.6/lib-tk','/usr/lib64/python2.6/site-packages','/usr/lib/python2.6/site-packages']
json module is existing within /usr/lib64/python2.6/ directory.
This python module (getActiveLocation.py) is imported inside a jython script (schedule_location.py) and when jython script is run, it is giving an import error for json module.
ImportError: no module named json
It looks like a sys.path issue.
I tried manually adding /usr/lib64/python2.6 to sys.path inside schedule_location.py via:
sys.path.append('/usr/lib64/python2.6')
Then the error changed to:
File "/usr/lib64/python2.6/json/__init__.py", line 108
from .decoder import JSONDecoder
^
SyntaxError: invalid syntax
Any idea why this error is happening? Your help is appreciated.
Vasily,
I am on a production system where I do not have any control! So upgrading jython is not an immediate solution for me :(.
I used simplejson as mentioned in the comment in Portable json module in jython
But here again, it is working when I run it in python. But when run from jython, it gives:
File "schedule_location.py", line 21, in ?
File "getActiveLocation.py", line 4, in ?
File "simplejson/__init__.py", line 113, in ?
File "simplejson/decoder.py", line 7
from .compat import fromhex, b, u, text_type, binary_type, PY3, unichr
^
SyntaxError: invalid syntax
To overcome this, I used:
from __future__ import absolute_import
But it gave:
File "schedule_location.py", line 21, in ?
File "getActiveLocation.py", line 1
SyntaxError: future feature absolute_import is not defined
I understand that this requires python 2.5 or more. But I am on Python 2.6

Probably you need
from __future__ import absolute_import
to make your code compatible with Python 3.x style imports.
Or try to remove "dot": from decoder import JSONDecoder. It should work in Python 2.6. Not sure about Jython.
EDIT: Found answer in the comment here: Portable json module in jython

I had the same SyntaxError when running a python script from a bash script. The solution was to specify the PYTHONPATH, e.g. PYTHONPATH = /usr/local/lib/python2.7. I also specified which python to use when running the python script, e.g. /usr/local/bin/python my_python_script.py.

Run python script from python using different python

I have a software that has python 2.5.5. I want to send a command that would start a script in python 2.7.5 and then proceed with the script.
I tried using
#!python2.7.5
and http://redsymbol.net/articles/env-and-python-scripts-version/
But I cant get it to work...
In my python 2.5.5 I can execute script as
execfile("c:/script/test.py")
The problem is that the 2.7.5 has a module comtypes + few other. I dont know how to install it for my 2.5.5 so I'm trying to start a separate script and run it under python27. Now another reason why I want it its because I want to take the load off program. I have 2 heavy tasks to perform. The second task is the one that need comptypes so sending it to external shell/app would do perfect trick. Is there a way to do it ?
I wish I could just type run("C:/Python27/python.exe % C:/script/test,py")
Thanks, bye.
Little update. I try to run
import os
os.system("\"C:\Python27\python.exe\" D:\test\runTest.py")
But I'm getting a quick pop up and close window saying that
Import Error : no module named site...
This works if I run from external shell but not from here :(
So I've tried another approach this time to add modules to python... in any case I run this :
import os
import sys
sys.path.append("C:/python27")
sys.path.append("C:/Python27/libs")
sys.path.append("C:/Python27/Lib")
sys.path.append("C:/Python27/Lib/logging")
sys.path.append("C:/Python27/Lib/site-packages")
sys.path.append("C:/Python27/Lib/ctypes")
sys.path.append("C:/Python27/DLLs")
import PyQt4
print PyQt4
import comtypes
import logging
but it crashes with C error...
Runtime Error :
Program: c:\Pr...
R6034
An application has made attempt to load the C runtime library incorectly.
blablabla....
How can I import it ? Maybe if I can import it I can run it directly from my app rather than starting separate python...
Traceback (most recent call last):
File "<string>", line 18, in <module>
File "C:\Python27\Lib\site-packages\comtypes\__init__.py", line 22, in <module>
from ctypes import *
File "C:\Python27\Lib\ctypes\__init__.py", line 10, in <module>
from _ctypes import Union, Structure, Array
ImportError: DLL load failed: A dynamic link library (DLL) initialization routine failed.
Another update to isseu
so I run now
import os
os.system("start cmd {D:\test\runTest.py}")
now this works and he open CMD with c:\Python27 as directory but he dont run the file... any hitns how to fix it?

Use "raw" strings so that you don't need to escape as much; I think the backslashes are what was breaking your code since backslash is considered an escape character except in raw strings.
Also, use the subprocess module. It makes it easy to avoid manually making a safe command string (the module takes care of that for you). All you need to do is pass it a list of arguments.
Your code would then look something like this:
import subprocess
proc = subprocess.Popen([r"C:\Python27\python.exe", r"D:\test\runTest.py"])
# then either do this
proc.wait() # wait until the process finishes
# or this
while True:
# NOTE: do something else here
# poll the process until it is done
if proc.poll() is not None:
break # break out of loop
See subprocess docs for Python 2 here. Be sure to check if a feature was added after Python 2.5 (the 2.5 docs aren't available online anymore AFAIK).
UPDATE:
I just noticed that you tried to use the Python 2.7 libraries and modules in your 2.5 code. This probably won't work due to new features added after 2.5. But it got me thinking how you might be able to make 2.7 work.
It may be that your Python2.7 install can't find its libraries; this is probably why you get the error Import Error : no module named site. You can do something like the above and modify the PYTHONPATH environment variable before starting the subprocess, like this:
import os
import subprocess
paths = [r"C:\python27", r"C:\python27\libs", r"C:\python27\Lib\site-packages", r"C:\python27\DLLs"]
paths += os.environ.get('PYTHONPATH', '').split(os.pathsep)
env27 = dict(os.environ)
env27['PYTHONPATH'] = os.pathsep.join(paths)
proc = subprocess.Popen([r"C:\Python27\python.exe", r"D:\test\runTest.py"], env=env27)

Imports working with raw file, but not in IDLE

UPDATE 10 Secs later
Fixed properly now, and thanks to JF and Gauden.
UPDATE
I have found a temporary fix by saving the IDLE file in the directory the other working file is in. (I would still like to know how to fix it entirely if I can.)
That's not a permanant fix, so if you want to try and help make it work wherever the file is saved, feel free.
This is the start of a python file:
#!/usr/bin/python
# -*- coding: utf-8 -*-
import wikipedia
import pagegenerators
import sys
import re
import pywikibot
from pywikibot import *
(You may have noticed it's a pywikipedia script, but I think that's irrelevent)
This file runs fine from the command line.
However, when I try and use IDLE to develop the script, or just use the IDLE interpreter, I get an error:
>>> import wikipedia
Traceback (most recent call last):
File "<pyshell#9>", line 1, in <module>
import wikipedia
ImportError: No module named wikipedia
I don't really have a clue why it isn't working.
I have also tried this:
>>> imp.find_module("wikipedia.py","f:/ake/pa/th/")
Traceback (most recent call last):
File "<pyshell#7>", line 1, in <module>
imp.find_module("wikipedia.py","f:/ake/pa/th/")
ImportError: No frozen submodule named f:/ake/pa/th/.wikipedia.py
The path given in the error log is the correct path to the wikipedia.py file, there's just that . before wikipedia.py.
I then tried adding the path to sys.path, but that didn't work either:
>>> import sys
>>> sys.path.append("c/users/adam/py")
#the same error...
Path to the module: `c:\users\joe_bloggs\py\wikipedia.pyc
Python executable: Command line:C:\Python27\python.exe, IDLE: C:\Python27\pythonw.exe
PYTHONPATH throws, in both:
Traceback (most recent call last):
File "<pyshell#20>", line 1, in <module>
print os.environ['PYTHONPATH'].split(os.pathsep)
File "C:\Python27\lib\os.py", line 423, in __getitem__
return self.data[key.upper()]
KeyError: 'PYTHONPATH'
OS: Windows 7
Python version: 2.7.2
A new PATH: IDLE, and Command Line:
C:\Program Files\Common Files\Microsoft Shared\Windows Live
C:\Program Files (x86)\Common Files\Microsoft Shared\Windows Live
C://Python27
C:\Program Files (x86)\IVI Foundation\VISA\WinNT\Bin
C:\Program Files (x86)\QuickTime\QTSystem\
C:\Program Files (x86)\Windows Live\Shared

EDIT The answer to the above question proved to be fairly simple, but I am editing this answer as a possible troubleshooting checklist for future reference, and as a checklist for others who may need to prepare questions of this nature in the future.
CLUE 1: What is the path to the module you are importing?
>>> import wikipedia
>>> print wikipedia.__file__
This will give you the path to the compiled module, and is one clue.
CLUE 2: What is the path to the Python executable?
(See also this question).
>>> import sys
>>> print sys.executable
Try this in the shell and in an IDLE script. If the two results are different, then you are using two Python interpreters and only one of them has a path that points to the wikipedia module.
CLUE 3: What is the sys.path?
Also repeat this in both shell and as a script in IDLE.
>>> print '\n'.join( sys.path )
(You may be able to use sys.path.append("d:/irectory/folder/is/in") to add that location to the sys.path. This should add that directory to the list of places Python looks for modules.)
CLUE 4: What is the PYTHONPATH and does it differ in the two environments?
(See also this answer).
Finally repeat this in both shell and as a script in IDLE.
>>> import os
>>> print '\n'.join( os.environ['PATH'].split(os.pathsep) )
Again note the two results (from shell and from IDLE) and see if there is difference in the PYTHONPATH in the two environments.
If all these tests prove inconclusive, I would add as much of this information as you can to your question as it would help give you specific further leads. Also add what OS you are using and any tracebacks that you get.

I had the same problem when trying to import a newly installed library on my Raspberry Pi. I followed all the instructions to install the library (Adafruit RHT Sensor) and it worked fine from the terminal. However, I couldn't get it to work from within IDLE.
It turned out that the problem was that the Raspberry Pi has both Python 2 and 3 installed. The install I'd done (using the 'python' command) only applied to Python 2. I had to perform another install using the 'python3' command to install it for Python 3. After that, I restarted IDLE and all worked fine.
The suggestion above to print the sys executable path helped point out the discrepancy:
import sys
print sys.executable