ImportError: cannot import name ReferencePattern

[simevo]

on debian buster:

python --version
Python 2.7.15+

to reproduce:

cd /tmp
mkdir q
virtualenv q
source q/bin/activate
pip install urubu
urubu build

trace:

Traceback (most recent call last):
  File "/tmp/q/bin/urubu", line 6, in <module>
    from urubu.main import main
  File "/tmp/q/local/lib/python2.7/site-packages/urubu/main.py", line 25, in <module>
    from urubu import project
  File "/tmp/q/local/lib/python2.7/site-packages/urubu/project.py", line 33, in <module>
    from urubu import readers, processors
  File "/tmp/q/local/lib/python2.7/site-packages/urubu/processors.py", line 31, in <module>
    from urubu import md_extensions
  File "/tmp/q/local/lib/python2.7/site-packages/urubu/md_extensions.py", line 31, in <module>
    from markdown.inlinepatterns import ReferencePattern, REFERENCE_RE, SHORT_REF_RE
ImportError: cannot import name ReferencePattern

[simevo]

here's the fix:

pip uninstall Markdown
pip install 'Markdown<3.0'

I guess you should put this in your pip package's setup.py

[LorenzoAncora]

Fixed by #87