There is ImportError: PyUnicodeUCS4_FromString according to the stack trace.
This happens when you have several versions of Python installed. Perhaps you are using a compiled module with a different interpreter than the one with which you compiled the module.
Python can be built with an internal Unicode representation of UCS2 or UCS4.
Newly created Python applications on Heroku use Python 3.6.2 runtime by default.
You can specify an arbitrary version of Python that will be used to run your expression. read docs python-runtimes heroku devcenter
source share