Develop Reference

Python gives error in anaconda after update

I have just tried to upgrade everything in my main environment to the latest version (using conda update --all). Everything went completely fine until I actually tried to run python. I got this error message:
Traceback (most recent call last):
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 579, in <module>
main()
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 562, in main
known_paths = venv(known_paths)
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 494, in venv
addsitepackages(known_paths, [sys.prefix])
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 349, in addsitepackages
addsitedir(sitedir, known_paths)
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 207, in addsitedir
addpackage(sitedir, name, known_paths)
File "C:\Users\Ayush\Anaconda3\lib\site.py", line 159, in addpackage
f = open(fullname, "r")
File "C:\Users\Ayush\Anaconda3\lib\_bootlocale.py", line 12, in getpreferredencoding
if sys.flags.utf8_mode:
AttributeError: 'sys.flags' object has no attribute 'utf8_mode'
As you can see, it looks like a problem with sys.flags. I tried googling this, but I couldn't find anyone with the same issue. I am using python 3.6.7 (python didn't update itself). This error message also appears if I try to run python in the command prompt. Here is the output of running conda update --all. Hope you can help!
EDIT: I found an issue on this issue on github here, but this doesn't give any explanations on how to fix this.
NOTE: I have also tried to install a new version of python using the installer, but that didn't work either.

I somehow did it - I re-installed Python, and then I tried using the command prompt, and it worked. It turned out that if I deleted my idea folder in Pycharm, it would work with the new version!

Running flake8 gives - AttributeError: 'OptionManager' object has no attribute 'config_options'

I installed flake8 using the following command.
pip3 install flake8
Executing flake8 from terminal gives the following error.
Traceback (most recent call last):
File "/home/bilesh/.local/bin/flake8", line 11, in <module>
sys.exit(main())
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/main/cli.py", line 18, in main
app.run(argv)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/main/application.py", line 394, in run
self._run(argv)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/main/application.py", line 381, in _run
self.initialize(argv)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/main/application.py", line 365, in initialize
self.register_plugin_options()
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/main/application.py", line 206, in register_plugin_options
self.check_plugins.register_options(self.option_manager)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/plugins/manager.py", line 496, in register_options
list(self.manager.map(register_and_enable))
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/plugins/manager.py", line 302, in map
yield func(self.plugins[name], *args, **kwargs)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/plugins/manager.py", line 492, in register_and_enable
call_register_options(plugin)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/plugins/manager.py", line 404, in generated_function
return method(optmanager, *args, **kwargs)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/plugins/manager.py", line 221, in register_options
add_options(optmanager)
File "/home/bilesh/.local/lib/python3.6/site-packages/flake8/_pyflakes.py", line 79, in add_options
parser.config_options.extend(['builtins', 'doctests',
AttributeError: 'OptionManager' object has no attribute 'config_options'
Found the following bug from 2016 but it seems to have been fixed.
https://github.com/PyCQA/flake8-import-order/issues/79
Not sure if I'm doing anything wrong here. Any help will be appreciated.
$ pip3 freeze | grep flake8
flake8==3.7.7
flake8-docstrings==1.3.0
flake8-polyfill==1.0.2

So, as per the comment posted by phd on this question, I did the following things.
Uninstall flake8: pip3 uninstall flake8
Clean directories: sudo rm -R /path/to/directory/flake8
Reinstall flake8: pip3 install flake8
And it worked :)

Installing pip for arcpy

I'm attempting to install pip for arcpy (arcgis 10.2 on windows 7). Running get-pip.py results in the following error message:
X:\python>python get-pip.py
Traceback (most recent call last):
File "get-pip.py", line 20061, in <module>
main()
File "get-pip.py", line 194, in main
bootstrap(tmpdir=tmpdir)
File "get-pip.py", line 82, in bootstrap
import pip
File "c:\temp\tmpou5fje\pip.zip\pip\__init__.py", line 26, in <module>
File "c:\temp\tmpou5fje\pip.zip\pip\utils\__init__.py", line 27, in <module>
File "c:\temp\tmpou5fje\pip.zip\pip\_vendor\pkg_resources\__init__.py", line 73, in <module>
File "c:\temp\tmpou5fje\pip.zip\pip\_vendor\packaging\specifiers.py", line 275, in <module>
File "c:\temp\tmpou5fje\pip.zip\pip\_vendor\packaging\specifiers.py", line 373, in Specifier
File "C:\Python27\ArcGIS10.2\Lib\re.py", line 190, in compile
return _compile(pattern, flags)
File "C:\Python27\ArcGIS10.2\Lib\re.py", line 242, in _compile
raise error, v # invalid expression
sre_constants.error: nothing to repeat
Using an administrator command prompt doesn't help. My real goal is to get win32com working under arcpy. I usual just copy the appropriate directories out of c:\python27\lib\site-packages to c:\python27\arcgis10.2\lib\site-packages to install a package under arcpy (why doesn't arcpy come with pip?) but that's not working for win32com, presumably do to a missing dll or other windows specific file.

I would recommend the following:
Get the setuptools module
Get the pip module`
And then run the following in command line (assuming windows)
path-to-python path-to-setuptools install
path-to-python path-to-pip install
I work on a closed network (away from the interwebs of old) and cannot use get-pip.py so I find it best to simply download the actual modules and hard install.
Keep us posted!

Copy get_pip.py to "C:\Python27\ArcGIS10.2", then perform command "python get-pip.py" in the directory.
Note that keep network connected in the process, so that auto-download and setup setuptools,wheels,etc.
Hope that can help you.

Try opening a CMD prompt and typing:
C:\Python27\ArcGIS10.2\python.exe -m pip install -U pip

Failure during project creation using 'djangocms' command

Django CMS 3.4.1
Django 1.10.2
pip modules: http://pastebin.com/vJWvZVfA
pip 8.1.2
Python 2.7.12
OS: Amazon Linux AMI release 2016.03
I'm new to Django CMS, Django, and Python. My previous CMS experience has been with WordPress and I'm try to try out Django CMS as an alternative to WordPress, but am getting an error that I can not seem to figure out. I have updated the pip modules and installed others as suggested in threads on StackOverflow, but to no avail.
I followed the tutorial the instructions, with the exception of the djangocms command, which is incorrect in the tutorial. (It's missing the -w flag.)
EDIT: As requested, here is the output with the --verbose flag added:
(env)[ec2-user#(redacted) tutorial-project]$ djangocms -d postgres://(redacted) -e no --permissions yes -l "en-CA, en-US, en, fr-CA, fr-FR" -p . --starting-page yes --verbose --utc mysite
Creating the project
Please wait while I install dependencies
Package install command: install django-cms<3.5 djangocms-admin-style>=1.2,<1.3 django-treebeard>=4.0,<5.0 psycopg2 djangocms-text-ckeditor>=3.2.1 djangocms-link>=1.8 djangocms-style>=1.7 djangocms-googlemap>=0.5 djangocms-snippet>=1.9 djangocms-video>=2.0 djangocms-column>=1.6 easy_thumbnails django-filer>=1.2 cmsplugin-filer>=1.1 Django<1.9 pytz django-classy-tags>=0.7 html5lib>=0.999999,<0.99999999 Pillow>=3.0 django-sekizai>=0.9 django-select2<5.0six
Command "python setup.py egg_info" failed with error code 1 in /tmp/pip-build-duWZSN/psycopg2/
The installation has failed.
*****************************************************************
Check documentation at https://djangocms-installer.readthedocs.io
*****************************************************************
Traceback (most recent call last):
File "/home/ec2-user/env/bin/djangocms", line 11, in <module>
sys.exit(execute())
File "/home/ec2-user/env/local/lib/python2.7/site-packages/djangocms_installer/main.py", line 33, in execute
verbose=config_data.verbose
File "/home/ec2-user/env/local/lib/python2.7/site-packages/djangocms_installer/install/__init__.py", line 91, in requirements
output = subprocess.check_output(['pip'] + args)
File "/usr/lib64/python2.7/subprocess.py", line 574, in check_output
raise CalledProcessError(retcode, cmd, output=output)
subprocess.CalledProcessError: Command '[u'pip', u'install', u'django-cms<3.5', u'djangocms-admin-style>=1.2,<1.3', u'django-treebeard>=4.0,<5.0', u'psycopg2', u'djangocms-text-ckeditor>=3.2.1', u'djangocms-link>=1.8', u'djangocms-style>=1.7', u'djangocms-googlemap>=0.5', u'djangocms-snippet>=1.9', u'djangocms-video>=2.0', u'djangocms-column>=1.6', u'easy_thumbnails', u'django-filer>=1.2', u'cmsplugin-filer>=1.1', u'Django<1.9', u'pytz', u'django-classy-tags>=0.7', u'html5lib>=0.999999,<0.99999999', u'Pillow>=3.0', u'django-sekizai>=0.9', u'django-select2<5.0six']' returned non-zero exit status 1
EDIT 2: (moved to answer)
EDIT 3:
After solving the first part, another error remains. I'll include it in this post since it still falls under the topic of the title:
Creating the project
Project creation command: /home/ec2-user/env/bin/python2.7 /home/ec2-user/env/bin/django-admin.py startproject mysite /home/ec2-user/tutorial-project
Database setup commands: /home/ec2-user/env/bin/python2.7 -W ignore manage.py migrate
Traceback (most recent call last):
File "manage.py", line 10, in <module>
execute_from_command_line(sys.argv)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 354, in execute_from_command_line
utility.execute()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/core/management/__init__.py", line 346, in execute
self.fetch_command(subcommand).run_from_argv(self.argv)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/core/management/base.py", line 394, in run_from_argv
self.execute(*args, **cmd_options)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/core/management/base.py", line 445, in execute
output = self.handle(*args, **options)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/core/management/commands/migrate.py", line 93, in handle
executor = MigrationExecutor(connection, self.migration_progress_callback)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/migrations/executor.py", line 19, in __init__
self.loader = MigrationLoader(self.connection)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/migrations/loader.py", line 47, in __init__
self.build_graph()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/migrations/loader.py", line 191, in build_graph
self.applied_migrations = recorder.applied_migrations()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/migrations/recorder.py", line 59, in applied_migrations
self.ensure_schema()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/migrations/recorder.py", line 49, in ensure_schema
if self.Migration._meta.db_table in self.connection.introspection.table_names(self.connection.cursor()):
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/backends/base/base.py", line 162, in cursor
cursor = self.make_debug_cursor(self._cursor())
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/backends/base/base.py", line 135, in _cursor
self.ensure_connection()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/backends/base/base.py", line 130, in ensure_connection
self.connect()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/backends/base/base.py", line 118, in connect
conn_params = self.get_connection_params()
File "/home/ec2-user/env/local/lib/python2.7/site-packages/django/db/backends/postgresql_psycopg2/base.py", line 158, in get_connection_params
"settings.DATABASES is improperly configured. "
django.core.exceptions.ImproperlyConfigured: settings.DATABASES is improperly configured. Please supply the NAME value.
The installation has failed.
*****************************************************************
Check documentation at https://djangocms-installer.readthedocs.io
*****************************************************************
Traceback (most recent call last):
File "/home/ec2-user/env/bin/djangocms", line 11, in <module>
sys.exit(execute())
File "/home/ec2-user/env/local/lib/python2.7/site-packages/djangocms_installer/main.py", line 41, in execute
django.setup_database(config_data)
File "/home/ec2-user/env/local/lib/python2.7/site-packages/djangocms_installer/django/__init__.py", line 388, in setup_database
output = subprocess.check_output(command, env=env)
File "/usr/lib64/python2.7/subprocess.py", line 574, in check_output
raise CalledProcessError(retcode, cmd, output=output)
subprocess.CalledProcessError: Command '['/home/ec2-user/env/bin/python2.7', u'-W', u'ignore', u'manage.py', u'migrate']' returned non-zero exit status 1
I'm going to guess that the problem lies in the message:
settings.DATABASES is improperly configured. Please supply the NAME value.
The installation has failed.
I'm using PostgreSQL, so I assume that the error is caused by the schema not being provided in the command argument. There was nothing in the guide that I saw indicating how to provide it, so I'll have to search some more.

The error message tells me absolutely nothing. It only tells me that Django tried to use pip to install something and for whatever reason it failed. In order to figure out what went wrong, try enabling verbose mode (python -v). If that gives the same output, or that isn't an option because you're using a program that calls Python (which it sounds like you are), let me know and prepare to go into the source code. Trust me, I have taken many a dive into source code for Python utilities, and as long as you don't do anything stupid (like delete a file) it's pretty hard to mess anything up. Even if you do you can always reinstall Django (or make a backup first). Don't worry about messing up your computer. You'd have to work hard to make Django do that!

Original error
The non-verbose error message indicates the error in a cryptic way, and using --verbose provides a more understandable message.
I was missing one required module (psycopg2) and four others were versions which were too new (easy_thumbnails, Django, html5lib, django-select2).
I uninstalled the four modules and then reinstalled them using the version requirement in the command. e.g. pip install 'Django<1.10'.
psycopg2 required extra steps, as I got an error message when trying to install it indicating that it could not find pg_config. Another SO answer advised that I just had to install postgresql-devel. After I did that, (sudo yum install postgresql-devel), I also uninstalled postgresql8-libs, as postgresql-devel came with a newer version. I didn't do it before since yum indicated a PHP dependency, and I wasn't sure if it would cause problems if I did.
Second error
Pretty simple. I was missing the /NAME component of the database URL (postgres://USER:PASSWORD#HOST:PORT/NAME).

Installing Fabric On Windows (Error No Module Called Readline)

I'm trying to use the Fabric 0.1.1 deploy tool (http://docs.fabfile.org/) on Windows and we're running into an issue with the readline module. I've been through various threads but can't seem to solve the issue. It's important because we can't deploy applications from Windows based machines.
C:\Documents and Settings\dev\Desktop\deploy>fab
Traceback (most recent call last):
File "C:\python\Scripts\fab-script.py", line 8, in <module>
load_entry_point('fabric==0.1.1', 'console_scripts', 'fab')()
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\pkg_resources.py"
, line 277, in load_entry_point
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\pkg_resources.py"
, line 2180, in load_entry_point
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\pkg_resources.py"
, line 1913, in load
File "build\bdist.win32\egg\fabric.py", line 25, in <module>
**ImportError: No module named readline**
Installing the module results in:
**easy_install readline**
Searching for readline
Reading http://pypi.python.org/simple/readline/
Reading http://www.python.org/
Best match: readline 2.6.4
Downloading http://pypi.python.org/packages/source/r/readline/readline-2.6.4.tar
.gz#md5=7568e8b78f383443ba57c9afec6f4285
Processing readline-2.6.4.tar.gz
Running readline-2.6.4\setup.py -q bdist_egg --dist-dir c:\docume~1\ji81b9~1.che
\locals~1\temp\easy_install-pzkz1a\readline-2.6.4\egg-dist-tmp-szs2ps
Traceback (most recent call last):
File "C:\python\Scripts\easy_install-script.py", line 8, in <module>
load_entry_point('setuptools==0.6c9', 'console_scripts', 'easy_install')()
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 1671, in main
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 1659, in with_ei_usage
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 1675, in <lambda>
File "c:\python\lib\distutils\core.py", line 152, in setup
dist.run_commands()
File "c:\python\lib\distutils\dist.py", line 975, in run_commands
self.run_command(cmd)
File "c:\python\lib\distutils\dist.py", line 995, in run_command
cmd_obj.run()
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 211, in run
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 446, in easy_install
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 476, in install_item
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 655, in install_eggs
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 930, in build_and_install
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\comman
d\easy_install.py", line 919, in run_setup
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\sandbo
x.py", line 27, in run_setup
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\sandbo
x.py", line 63, in run
File "c:\python\lib\site-packages\setuptools-0.6c9-py2.6.egg\setuptools\sandbo
x.py", line 29, in <lambda>
File "setup.py", line 93, in <module>
AttributeError: 'module' object has no attribute 'symlink'
Has anybody solved this issue or can anybody suggest a workaround?

The readline module you are trying to install with easy_install is for OS X, not windows. There are Windows-compatible replacements for readline out there but perhaps you should first try updating fabric itself to a more current version (0.9 is out there now).
Grepping the source of the 0.9 version does not find any dependencies on readline.

Following these steps exactly worked for me:
1) Installed using the MSI installer for x86 from here.
2) Installed in the default C:\Python27 directory.
3) Create a new directory: C:\Python27\Scripts
4) Added C:\Python27 and C:\Python27\Scripts to the system path:
5) Download the distribute_setup.py from here into C:\Python27\Scripts
6) Open a command line, navigate to C:\Python27\Scripts, run: 'python distribute_setup.py'
7) now run 'easy_install pip'
8) now run 'pip install fabric'
9) You should get an error saying PyCrypto couldn't install. You can download the pre-build Windows binary from here. Run this to install PyCrypto.
10) run 'pip install fabric' again and it should say everything is installed.
11) in a different directory (let's say c:\dev\hello) create a fabfile.py and add the following code:
def hello(name="world"):
print("Hello %s!" % name)
12) cd to this directory and run 'fab hello:working'. You should see output say
Hello working!
Done.

Give this readline a try. It is a module for Windows that allows additional features in IPython that aren't native and might work with what you are trying to do.

0.1.1 is an older version, I believe. I have no problem installing Fabric on Windows with ActivePython (w/ PyPM):
C:\> pypm install fabric
Ready to perform these actions:
The following packages will be installed:
fabric-0.9.0 pycrypto-2.0.1
Get: [pypm.activestate.com] fabric 0.9.0-1
Get: [pypm.activestate.com] pycrypto 2.0.1-1
Installing fabric-0.9.0
Fixing script C:\Users\sridharr\AppData\Roaming\Python\Scripts\fab-script.py
Installing pycrypto-2.0.1

Download and run easy_install installer for your python version from http://pypi.python.org/pypi/setuptools#downloads . ie: setuptools-0.6c11.win32-py2.6.exe
On the command prompt, lauch easy_install -U fabric to install the last fabric release.

Readline should be available with Cygwin, if you want to move your entire stack in that direction.