Unable to import scanpy on CentOS 7 with Python 3.9

[dm8000]

• [ x] I have checked that this issue has not already been reported.
• [x ] I have confirmed this bug exists on the latest version of scanpy.
• [ ] (optional) I have confirmed this bug exists on the master branch of scanpy.

---

Hello

I installed scanpy with no errors or warnings. When I tried to import it, I get the error

import scanpy as sc

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-1-0074c9bc0b31> in <module>
----> 1 import scanpy as sc

path/lib/python3.9/site-packages/scanpy/__init__.py in <module>
      6     from ._utils import check_versions
      7 
----> 8     check_versions()
      9     del check_versions, within_flit
     10 

path/lib/python3.9/site-packages/scanpy/_utils/__init__.py in check_versions()
     47     umap_version = pkg_version("umap-learn")
     48 
---> 49     if version.parse(anndata_version) < version.parse('0.6.10'):
     50         from .. import __version__
     51 

path/lib/python3.9/site-packages/packaging/version.py in parse(version)
     47     """
     48     try:
---> 49         return Version(version)
     50     except InvalidVersion:
     51         return LegacyVersion(version)

path/lib/python3.9/site-packages/packaging/version.py in __init__(self, version)
    262 
    263         # Validate the version and parse it into pieces
--> 264         match = self._regex.search(version)
    265         if not match:
    266             raise InvalidVersion(f"Invalid version: '{version}'")

TypeError: expected string or bytes-like object

Versions

linux

! cat /etc/os-release

NAME="CentOS Linux"
VERSION="7 (Core)"
ID="centos"
ID_LIKE="rhel fedora"
VERSION_ID="7"
PRETTY_NAME="CentOS Linux 7 (Core)"
ANSI_COLOR="0;31"
CPE_NAME="cpe:/o:centos:centos:7"
HOME_URL="https://www.centos.org/"
BUG_REPORT_URL="https://bugs.centos.org/"

CENTOS_MANTISBT_PROJECT="CentOS-7"
CENTOS_MANTISBT_PROJECT_VERSION="7"
REDHAT_SUPPORT_PRODUCT="centos"
REDHAT_SUPPORT_PRODUCT_VERSION="7"

python

sys.version_info(major=3, minor=9, micro=2, releaselevel='final', serial=0)

[giovp]

hi @dm8000 did you install it with pip or conda? I would try to re installl with either of the two methods.

[dm8000]

Hello @giovp

I used pip for the installation

[Zethson]

Could you please ensure that you are attempting to import scanpy in a fresh, clean environment? Also, what's your Python version?

[dm8000]

Could you please ensure that you are attempting to import scanpy in a fresh, clean environment? Also, what's your Python version?

the version would be 3.9.2

and I did try importing it on clean environment

[Zethson]

@dm8000 does this issue still persist? If yes, please reopen.

I'd then also like to see the full pip list output