ImportError while loading conftest.py while using pytest

Hello, I am an Outreachy applicant and I am preparing my development environment to contribute to Jax. I have installed the Jax and system requirements as indicated in the contribution guide. Python version = 3.8.10. Jax installed on CPU. But when I make sure that the tests pass correctly, I get the following error:

ImportError while loading conftest '/home/carcablop/jax/conftest.py'.
conftest.py:16: in <module>
    import jax
E     File "/home/carcablop/jax/jax/__init__.py", line 27
E       _warn(f"cloud_tpu_init failed: {repr(exc)}\n This a JAX bug; please report "
E                                                                                  ^
E   SyntaxError: invalid syntax

When I run only “pytest” out of the root folder I get the following error:

============================= test session starts ==============================
platform linux2 -- Python 2.7.18, pytest-4.6.9, py-1.8.1, pluggy-0.13.0
rootdir: /home/carcablop
collected 0 items / 1 errors                                                   

==================================== ERRORS ====================================
________________________ ERROR collecting test session _________________________
/usr/lib/python2.7/dist-packages/py/_path/common.py:383: in visit
    for x in Visitor(fil, rec, ignore, bf, sort).gen(self):
/usr/lib/python2.7/dist-packages/py/_path/common.py:425: in gen
    if p.check(dir=1) and (rec is None or rec(p))])
/usr/lib/python2.7/dist-packages/_pytest/main.py:667: in _recurse
    ihook = self.gethookproxy(dirpath)
/usr/lib/python2.7/dist-packages/_pytest/main.py:482: in gethookproxy
    my_conftestmodules = pm._getconftestmodules(fspath)
/usr/lib/python2.7/dist-packages/_pytest/config/__init__.py:424: in _getconftestmodules
    mod = self._importconftest(conftestpath.realpath())
/usr/lib/python2.7/dist-packages/_pytest/config/__init__.py:463: in _importconftest
    raise ConftestImportFailure(conftestpath, sys.exc_info())
E   ConftestImportFailure: (local('/home/carcablop/jax/conftest.py'), (<type 'exceptions.SyntaxError'>, SyntaxError('invalid syntax', ('/home/carcablop/jax/jax/__init__.py', 27, 78, '  _warn(f"cloud_tpu_init failed: {repr(exc)}\\n This a JAX bug; please report "\n')), <traceback object at 0x7efcdcbc47d0>))
!!!!!!!!!!!!!!!!!!! Interrupted: 1 errors during collection !!!!!!!!!!!!!!!!!!!!
=========================== 1 error in 0.10 seconds ===========================

Could someone help me with this error? , Maybe I have missed something in the configuration or installation?

Thank you so much. Carolina

[carcablop]

Indeed, I had libtpu installed, I deleted it and the test is running without errors. Thank you.

[jakevdp]

To see if you have libtpu installed and, if so, print its location, you can run this:

$ python3 -c "import libtpu; print(libtpu.__path__)"

This may have been installed, for example, if you accidentally followed the Cloud TPU installation instructions here: https://github.com/google/jax#pip-installation-google-cloud-tpu