Pyrsistent error when upgrading from 2.0

Hello,

yesterday I succeeded to upgrade an old indico 1.2 version (which was on an old OpenSuSE machine) to 2.0 on a new machine (with CentOS Linux 7)
Next step was to upgrade from 2.0 to newer version.
I used the command on this page: https://docs.getindico.io/en/latest/installation/upgrade/

But the command pip install -U indico stops with the message in red:
pyrsistent requires Python ‘>=3.5’ but the running Python is 2.7.5

Any solution??

Cheers, Henk

Output I get:

source ~/.venv/bin/activate

(.venv) [indico@rock35 ~]$ export PATH="$PATH:/usr/pgsql-9.6/bin"

(.venv) [indico@rock35 ~]$ pip install -U indico

Collecting indico
  Downloading https://files.pythonhosted.org/packages/d0/d3/99f9e863ba6baf6907c56cbbcd52a7835e3bee3403ec0c7c9508b4d2281b/indico-2.3.2-py2-none-any.whl (52.5MB)
    100% |████████████████████████████████| 52.5MB 18kB/s
Collecting PyYAML==5.3.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/64/c2/b80047c7ac2478f9501676c988a5411ed5572f35d1beff9cae07d321512c/PyYAML-5.3.1.tar.gz (269kB)
    100% |████████████████████████████████| 276kB 3.6MB/s
Collecting Babel==2.8.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/15/a1/522dccd23e5d2e47aed4b6a16795b8213e3272c7506e625f2425ad025a19/Babel-2.8.0-py2.py3-none-any.whl (8.6MB)
    100% |████████████████████████████████| 8.6MB 115kB/s
Collecting marshmallow==3.0.0rc5 (from indico)
  Downloading https://files.pythonhosted.org/packages/fd/91/06f9a52d8647fc7bebf24e3745f8eea4e2495006676353d3494d2f1afa93/marshmallow-3.0.0rc5-py2.py3-none-any.whl (44kB)
    100% |████████████████████████████████| 51kB 8.5MB/s
Collecting click==7.1.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/d2/3d/fa76db83bf75c4f8d338c2fd15c8d33fdd7ad23a9b5e57eb6c5de26b430e/click-7.1.2-py2.py3-none-any.whl (82kB)
    100% |████████████████████████████████| 92kB 8.4MB/s
Requirement already up-to-date: zope.interface==3.8.0 in ./.venv/lib/python2.7/site-packages (from indico)
Requirement already up-to-date: Flask-PluginEngine==0.3.1 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting psycopg2==2.8.6 (from indico)
  Downloading https://files.pythonhosted.org/packages/fd/ae/98cb7a0cbb1d748ee547b058b14604bd0e9bf285a8e0cc5d148f8a8a952e/psycopg2-2.8.6.tar.gz (383kB)
    100% |████████████████████████████████| 389kB 2.7MB/s
Collecting pywebpack==1.0.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/48/b0/852f93d66c98c61527f0231f2f42cb51e1f80ff7462d794ea63f75397165/pywebpack-1.0.1-py2.py3-none-any.whl
Collecting contextlib2==0.6.0.post1 (from indico)
  Downloading https://files.pythonhosted.org/packages/85/60/370352f7ef6aa96c52fb001831622f50f923c1d575427d021b8ab3311236/contextlib2-0.6.0.post1-py2.py3-none-any.whl
Collecting email-validator==1.1.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/8b/f5/26dc56e8e5b3441e766c8c359be9a28d2355902ab8b2140a2d5988da675e/email_validator-1.1.1-py2.py3-none-any.whl
Requirement already up-to-date: blinker==1.4 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting Flask-OAuthlib==0.9.5 (from indico)
  Downloading https://files.pythonhosted.org/packages/ec/58/c945c8d11afeecda47a00b4324e745598358abdb8d0175ad7c7848da8b68/Flask_OAuthlib-0.9.5-py2-none-any.whl (40kB)
    100% |████████████████████████████████| 40kB 6.6MB/s
Requirement already up-to-date: terminaltables==3.1.0 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting pytest-cov==2.10.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/e5/18/401594af67eda194a8b9167208621761927c937db7d60292608342bbac0a/pytest_cov-2.10.1-py2.py3-none-any.whl
Collecting bleach==3.1.5 (from indico)
  Downloading https://files.pythonhosted.org/packages/9a/1e/7d6cb3b27cd2c490558349ca5d5cc05b390b017da1c704cac807ac8bd9fb/bleach-3.1.5-py2.py3-none-any.whl (151kB)
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Collecting Flask-WTF==0.14.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/36/a9/8c01171066bd7a524ee005d81bb4a8aa446ab178043a1ad6cb5dc8f0bd83/Flask_WTF-0.14.3-py2.py3-none-any.whl
Collecting html2text==2019.8.11 (from indico)
  Downloading https://files.pythonhosted.org/packages/f0/68/2bdc9ff2202b53d2fd6321be48d1effca0f679f0797701017df5be26bd82/html2text-2019.8.11-py2.py3-none-any.whl
Collecting MarkupSafe==1.1.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/fb/40/f3adb7cf24a8012813c5edb20329eb22d5d8e2a0ecf73d21d6b85865da11/MarkupSafe-1.1.1-cp27-cp27mu-manylinux1_x86_64.whl
Collecting Flask-Multipass<0.4-dev,>=0.3.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/6c/4f/d58dee45146ae2ade28b9124638985e29b0654b7d3b517839775fe95663e/Flask_Multipass-0.3.2-py2.py3-none-any.whl
Collecting flask-marshmallow==0.11.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/19/0a/8ca7470cb74e0a31eb902b610867d5e4c86ff03a86203f7fd580d57a9850/flask_marshmallow-0.11.0-py2.py3-none-any.whl
Requirement already up-to-date: prompt-toolkit<2.0.0,>=1.0.14 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting Flask-SQLAlchemy==2.4.4 (from indico)
  Downloading https://files.pythonhosted.org/packages/af/4b/3dd83c3e2c6e3034b804d971952e0120606506f153990cc56d2d33173b72/Flask_SQLAlchemy-2.4.4-py2.py3-none-any.whl
Collecting celery==4.4.7 (from indico)
  Downloading https://files.pythonhosted.org/packages/c8/0c/609e3611d20c9f8d883852d1be5516671f630fb08c8c1e56911567dfba7b/celery-4.4.7-py2.py3-none-any.whl (427kB)
    100% |████████████████████████████████| 430kB 2.4MB/s
Requirement already up-to-date: pyPdf==1.13 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting Flask-BabelEx==0.9.4 (from indico)
  Downloading https://files.pythonhosted.org/packages/85/e7/217fb37ccd4bd93cd0f002028fb7c5fdf6ee0063a6beb83e43cd903da46e/Flask-BabelEx-0.9.4.tar.gz (43kB)
    100% |████████████████████████████████| 51kB 8.4MB/s
Collecting Flask-Caching==1.7.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/bd/4e/c701bdcd566f26187398cf058ad2ca14c8b2f50b17a17f9076794ae2f8db/Flask_Caching-1.7.2-py2.py3-none-any.whl
Requirement already up-to-date: enum34 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting Markdown==3.1.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/c0/4e/fd492e91abdc2d2fcb70ef453064d980688762079397f779758e055f6575/Markdown-3.1.1-py2.py3-none-any.whl (87kB)
    100% |████████████████████████████████| 92kB 7.3MB/s
Collecting feedgen==0.9.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/0b/60/7714c7f1339e063ad2e0964870797610c23191c180fc2713be100cc82d1a/feedgen-0.9.0.tar.gz (217kB)
    100% |████████████████████████████████| 225kB 3.9MB/s
Collecting pytest-localserver==0.5.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/6c/b3/db8f8700718fbefaa2e8b2ef690fec147e560ce92e2300cdb3ff462d313c/pytest-localserver-0.5.0.tar.gz
Collecting mock==3.0.5 (from indico)
  Downloading https://files.pythonhosted.org/packages/05/d2/f94e68be6b17f46d2c353564da56e6fb89ef09faeeff3313a046cb810ca9/mock-3.0.5-py2.py3-none-any.whl
Collecting pycountry==19.8.18 (from indico)
  Downloading https://files.pythonhosted.org/packages/16/b6/154fe93072051d8ce7bf197690957b6d0ac9a21d51c9a1d05bd7c6fdb16f/pycountry-19.8.18.tar.gz (10.0MB)
    100% |████████████████████████████████| 10.0MB 96kB/s
Collecting flask-webpackext==1.0.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/c1/d1/60d1a90be326b7d1d87e4a0d8e5aeadb843a8766642138fea3a802511a66/flask_webpackext-1.0.2-py2.py3-none-any.whl
Collecting simplejson==3.17.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/b2/de/93ca9de15e533f1950eb219f1fbb248361d5d572cb693bb47dca422c87f1/simplejson-3.17.2-cp27-cp27mu-manylinux1_x86_64.whl (131kB)
    100% |████████████████████████████████| 133kB 6.6MB/s
Collecting pytest-mock==2.0.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/99/95/d108de3eed0ae29d98c94c918c1245713e7f222dead2d77c24bc4ca7ca0c/pytest_mock-2.0.0-py2.py3-none-any.whl
Collecting pytz (from indico)
  Downloading https://files.pythonhosted.org/packages/89/06/2c2d3034b4d6bf22f2a4ae546d16925898658a33b4400cfb7e2c1e2871a3/pytz-2020.5-py2.py3-none-any.whl (510kB)
    100% |████████████████████████████████| 512kB 2.1MB/s
Collecting SQLAlchemy==1.3.19 (from indico)
  Downloading https://files.pythonhosted.org/packages/9b/b8/4e1b11c6ebc98da7445ed89ce5d8b6e2b94f26e37407112fb272c6cdd7ca/SQLAlchemy-1.3.19-cp27-cp27mu-manylinux1_x86_64.whl (1.2MB)
    100% |████████████████████████████████| 1.2MB 842kB/s
Requirement already up-to-date: wsgiref==0.1.2 in /usr/lib64/python2.7 (from indico)
Collecting icalendar==4.0.7 (from indico)
  Downloading https://files.pythonhosted.org/packages/c5/14/85ffbeefb591e8be0d51e4611750653549f60b27221ce6b0f9c724b3f5c0/icalendar-4.0.7-py2.py3-none-any.whl (74kB)
    100% |████████████████████████████████| 81kB 8.3MB/s
Collecting hiredis==1.1.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/59/13/5c620b1324506fc886113793291630c340ddecad88f05dcbf16376eeccf9/hiredis-1.1.0-cp27-cp27mu-manylinux1_x86_64.whl (58kB)
    100% |████████████████████████████████| 61kB 8.1MB/s
Requirement already up-to-date: kombu<4.7,>=4.6.10 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting redis==3.5.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/a7/7c/24fb0511df653cf1a5d938d8f5d19802a88cef255706fdda242ff97e91b7/redis-3.5.3-py2.py3-none-any.whl (72kB)
    100% |████████████████████████████████| 81kB 8.5MB/s
Collecting python-dateutil==2.8.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/d4/70/d60450c3dd48ef87586924207ae8907090de0b306af2bce5d134d78615cb/python_dateutil-2.8.1-py2.py3-none-any.whl (227kB)
    100% |████████████████████████████████| 235kB 4.1MB/s
Requirement already up-to-date: termcolor==1.1.0 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting freezegun==0.3.15 (from indico)
  Downloading https://files.pythonhosted.org/packages/17/5d/1b9d6d3c7995fff473f35861d674e0113a5f0bd5a72fe0199c3f254665c7/freezegun-0.3.15-py2.py3-none-any.whl
Requirement already up-to-date: packaging<21,>=20.4 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting marshmallow-sqlalchemy==0.18.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/35/b0/60b51e7e4096551d7b3ee636ce4dd5034b6889763b7ddc98dc2057b31eef/marshmallow_sqlalchemy-0.18.0-py2.py3-none-any.whl
Collecting Pillow==6.2.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/12/ad/61f8dfba88c4e56196bf6d056cdbba64dc9c5dfdfbc97d02e6472feed913/Pillow-6.2.2-cp27-cp27mu-manylinux1_x86_64.whl (2.1MB)
    100% |████████████████████████████████| 2.1MB 477kB/s
Collecting pytest==4.6.11 (from indico)
  Downloading https://files.pythonhosted.org/packages/70/c7/e8cb4a537ee4fc497ac80a606a667fd1832f28ad3ddbfa25bf30473eae13/pytest-4.6.11-py2.py3-none-any.whl (231kB)
    100% |████████████████████████████████| 235kB 4.3MB/s
Collecting lxml[html5]==4.5.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/d1/2d/642ef7013aa56af52e14b5b7d53c5d591e6d038c9688e06d0f2a20ed26b2/lxml-4.5.2-cp27-cp27mu-manylinux1_x86_64.whl (5.5MB)
    100% |████████████████████████████████| 5.5MB 187kB/s
Requirement already up-to-date: indico-fonts==1.1 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting Flask==1.1.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/f2/28/2a03252dfb9ebf377f40fba6a7841b47083260bf8bd8e737b0c6952df83f/Flask-1.1.2-py2.py3-none-any.whl (94kB)
    100% |████████████████████████████████| 102kB 7.7MB/s
Collecting xlsxwriter==1.3.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/2b/98/17875723b6814fc4d0fc03f0997ee00de2dbd78cf195e2ec3f2c9c789d40/XlsxWriter-1.3.3-py2.py3-none-any.whl (144kB)
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Collecting marshmallow-enum==1.5.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/c6/59/ef3a3dc499be447098d4a89399beb869f813fee1b5a57d5d79dee2c1bf51/marshmallow_enum-1.5.1-py2.py3-none-any.whl
Collecting Werkzeug==0.16.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/c2/e4/a859d2fe516f466642fa5c6054fd9646271f9da26b0cac0d2f37fc858c8f/Werkzeug-0.16.1-py2.py3-none-any.whl (327kB)
    100% |████████████████████████████████| 327kB 3.2MB/s
Collecting qrcode==6.1 (from indico)
  Downloading https://files.pythonhosted.org/packages/42/87/4a3a77e59ab7493d64da1f69bf1c2e899a4cf81e51b2baa855e8cc8115be/qrcode-6.1-py2.py3-none-any.whl
Requirement already up-to-date: colorclass==2.2.0 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting reportlab==3.5.49 (from indico)
  Downloading https://files.pythonhosted.org/packages/b6/12/26b047fa2df39422c02a2a5be19a9bf4491c13f9a67287d5c9445b9d743e/reportlab-3.5.49-cp27-cp27mu-manylinux1_x86_64.whl (2.6MB)
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Collecting itsdangerous==1.1.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/76/ae/44b03b253d6fade317f32c24d100b3b35c2239807046a4c953c7b89fa49e/itsdangerous-1.1.0-py2.py3-none-any.whl
Requirement already up-to-date: requests-oauthlib<1.2.0 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting alembic==1.4.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/60/1e/cabc75a189de0fbb2841d0975243e59bde8b7822bacbb95008ac6fe9ad47/alembic-1.4.2.tar.gz (1.1MB)
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Requirement already up-to-date: ipython<6,>=5.4.1 in ./.venv/lib/python2.7/site-packages (from indico)
Requirement already up-to-date: pojson==0.7 in ./.venv/lib/python2.7/site-packages (from indico)
Requirement already up-to-date: certifi in ./.venv/lib/python2.7/site-packages (from indico)
Collecting WTForms[email,ipaddress]==2.3.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/e0/31/614fc7dc7d76005b0acb8c0c8920d962b83d7422b4ba912886dfb63f86ff/WTForms-2.3.3-py2.py3-none-any.whl (169kB)
    100% |████████████████████████████████| 174kB 5.5MB/s
Collecting requests==2.24.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/45/1e/0c169c6a5381e241ba7404532c16a21d86ab872c9bed8bdcd4c423954103/requests-2.24.0-py2.py3-none-any.whl (61kB)
    100% |████████████████████████████████| 71kB 9.1MB/s
Collecting jsonschema==3.2.0 (from indico)
  Downloading https://files.pythonhosted.org/packages/c5/8f/51e89ce52a085483359217bc72cdbf6e75ee595d5b1d4b5ade40c7e018b8/jsonschema-3.2.0-py2.py3-none-any.whl (56kB)
    100% |████████████████████████████████| 61kB 8.3MB/s
Collecting Jinja2==2.11.2 (from indico)
  Downloading https://files.pythonhosted.org/packages/30/9e/f663a2aa66a09d838042ae1a2c5659828bb9b41ea3a6efa20a20fd92b121/Jinja2-2.11.2-py2.py3-none-any.whl (125kB)
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Requirement already up-to-date: translitcodec==0.4.0 in ./.venv/lib/python2.7/site-packages (from indico)
Collecting webargs==5.5.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/42/04/6c37af320f42444c83e072609a69571e51229e77e36f1d5a84e68cf826c1/webargs-5.5.3-py2-none-any.whl
Collecting bcrypt==3.1.7 (from indico)
  Downloading https://files.pythonhosted.org/packages/ad/36/9a0227d048e98409f012570f7bef8a8c2373b9c9c5dfbf82963cbae05ede/bcrypt-3.1.7-cp27-cp27mu-manylinux1_x86_64.whl (59kB)
    100% |████████████████████████████████| 61kB 7.5MB/s
Requirement already up-to-date: ipaddress in ./.venv/lib/python2.7/site-packages (from indico)
Collecting idna==2.9 (from indico)
  Downloading https://files.pythonhosted.org/packages/89/e3/afebe61c546d18fb1709a61bee788254b40e736cff7271c7de5de2dc4128/idna-2.9-py2.py3-none-any.whl (58kB)
    100% |████████████████████████████████| 61kB 7.8MB/s
Collecting Flask-Migrate==2.5.3 (from indico)
  Downloading https://files.pythonhosted.org/packages/e5/64/c75f173ba5420f5174be6f04dfa8d8250d4808c12a9cd781e84c0b31684f/Flask_Migrate-2.5.3-py2.py3-none-any.whl
Requirement already up-to-date: setuptools in ./.venv/lib/python2.7/site-packages (from zope.interface==3.8.0->indico)
Collecting node-semver>=0.1.1 (from pywebpack==1.0.1->indico)
  Downloading https://files.pythonhosted.org/packages/8a/2f/88e7e0f758b7a99c95556dae788a07ce9379489263f8e5352587328ce606/node-semver-0.7.0.tar.gz
Collecting pynpm>=0.1.0 (from pywebpack==1.0.1->indico)
  Downloading https://files.pythonhosted.org/packages/65/23/9180c01162e046d17808a01c3f5d81e51276a1b4c26d73dbceb7c282026b/pynpm-0.1.2-py2.py3-none-any.whl
Collecting dnspython>=1.15.0 (from email-validator==1.1.1->indico)
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pyrsistent requires Python '>=3.5' but the running Python is 2.7.5

I think you may have a very outdated version of pip or setuptools which does not take python version requirements into account. Try if running pip install -U pip setuptools before upgrading indico helps.

Message I get:

pip install -U pip setuptools
Requirement already up-to-date: pip in ./.venv/lib/python2.7/site-packages
Requirement already up-to-date: setuptools in ./.venv/lib/python2.7/site-packages

There must be something wrong with your environment… if you check PyPI, the pyrsistent version your pip is trying to install has been yanked because it was broken (missing metadata restricting it to Python 3), so pyrsistent>=0.14.0 should not even try installing it at all.

Maybe try clearing the pip cache by deleting the ~/.cache/pip folder. Alternatively, delete and recreate the virtualenv and then pip install indico in there. That way you also get rid of the leftover indico-zodbimport dependencies.

:+1:

removing the ~/.venv directory and recreating it with virtualenv ~/.venv solved the problem.

Thanks for the support.