sagemath 9.0 has some errors now

[hongwen luo]

lhw@lhw:~$ sage
┌────────────────────────────────────────────────────────────────────┐
│ SageMath version 9.0, Release Date: 2020-01-01 │
│ Using Python 3.8.6. Type "help()" for help. │
└────────────────────────────────────────────────────────────────────┘
Traceback (most recent call last):
  File "/usr/share/sagemath/bin/sage-ipython", line 12, in <module>
    from sage.repl.interpreter import SageTerminalApp
  File "/usr/lib/python3/dist-packages/sage/repl/interpreter.py", line 105, in <module>
    from sage.repl.preparse import preparse, containing_block
  File "/usr/lib/python3/dist-packages/sage/repl/preparse.py", line 227, in <module>
    from sage.repl.load import load_wrap
  File "/usr/lib/python3/dist-packages/sage/repl/load.py", line 19, in <module>
    from sage.cpython.string import str_to_bytes, bytes_to_str, FS_ENCODING
ModuleNotFoundError: No module named 'sage.cpython.string'
lhw@lhw:~$ uname -a
Linux lhw 5.8.0-19-generic #20-Ubuntu SMP Fri Sep 11 09:08:26 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux
lhw@lhw:~$

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.