Hi,

i'm trying to install python-docTR on S390x, but dependency pypdfium2 build failed.
i'm tring to install pypdfium2 from pip getting the following error .

`pip install pypdfium2
Collecting pypdfium2
Downloading pypdfium2-4.30.0.tar.gz (140 kB)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 140.2/140.2 kB 3.8 MB/s eta 0:00:00
Installing build dependencies ... done
Getting requirements to build wheel ... error
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> [18 lines of output]
Traceback (most recent call last):
File "/usr/local/lib/python3.10/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 353, in
main()
File "/usr/local/lib/python3.10/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 335, in main
json_out['return_val'] = hook(**hook_input['kwargs'])
File "/usr/local/lib/python3.10/dist-packages/pip/_vendor/pyproject_hooks/_in_process/_in_process.py", line 118, in get_requires_for_build_wheel
return hook(config_settings)
File "/tmp/pip-build-env-iw42b6xf/overlay/local/lib/python3.10/dist-packages/setuptools/build_meta.py", line 325, in get_requires_for_build_wheel
return self._get_build_requires(config_settings, requirements=['wheel'])
File "/tmp/pip-build-env-iw42b6xf/overlay/local/lib/python3.10/dist-packages/setuptools/build_meta.py", line 295, in _get_build_requires
self.run_setup()
File "/tmp/pip-build-env-iw42b6xf/overlay/local/lib/python3.10/dist-packages/setuptools/build_meta.py", line 311, in run_setup
exec(code, locals())
File "", line 161, in
File "", line 152, in main
File "/tmp/pip-install-96eku2nd/pypdfium2_5345d99864474a78ac39d1b0c222be99/setupsrc/pypdfium2_setup/packaging_base.py", line 610, in parse_pl_spec
raise RuntimeError(f"No pre-built binaries available for {Host}. You may place custom binaries & bindings in data/sourcebuild and install with {PlatSpec_EnvVar}=sourcebuild.")
RuntimeError: No pre-built binaries available for <Host: linux s390x, glibc 2.35>. You may place custom binaries & bindings in data/sourcebuild and install with PDFIUM_PLATFORM=sourcebuild.
[end of output]

note: This error originates from a subprocess, and is likely not a problem with pip.
error: subprocess-exited-with-error

× Getting requirements to build wheel did not run successfully.
│ exit code: 1
╰─> See above for output.

note: This error originates from a subprocess, and is likely not a problem with pip.`