Version-Release number of selected component:
system-config-language-3.4.2-3.fc27

Additional info:
reporter:       libreport-2.9.3
cmdline:        /usr/bin/python3 /usr/share/system-config-language/system-config-language.py
crash_function: perform
exception_type: librepo.LibrepoException
executable:     /usr/share/system-config-language/system-config-language.py
kernel:         4.14.6-300.fc27.x86_64
runlevel:       N 5
type:           Python3
uid:            0

Truncated backtrace:
repo.py:926:load:dnf.exceptions.RepoError: Failed to synchronize cache for repo 'updates'

Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 229, in _perform
    return super(_Handle, self).perform(result)
  File "/usr/lib64/python3.6/site-packages/librepo/__init__.py", line 1522, in perform
    _librepo.Handle.perform(self, result)
librepo.LibrepoException: (8, "Cannot prepare internal mirrorlist: Curl error (6): Couldn't resolve host name for https://mirrors.fedoraproject.org/metalink?repo=updates-released-f27&arch=x86_64 [Could not resolve host: mirrors.fedoraproject.org]", 'An Curl handle error')

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 914, in load
    self._handle_load(handle)
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 657, in _handle_load
    return self._handle_load_core(handle)
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 670, in _handle_load_core
    result = handle._perform()
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 233, in _perform
    raise _DetailedLibrepoError(exc, source)
dnf.repo._DetailedLibrepoError

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/share/system-config-language/language_gui.py", line 307, in ok_btn
    installed = self.instpkg.install_packages3(dlang)
  File "/usr/share/system-config-language/install_packages3.py", line 237, in install_packages3
    self.base.fill_sack()
  File "/usr/lib/python3.6/site-packages/dnf/base.py", line 353, in fill_sack
    self._add_repo_to_sack(r)
  File "/usr/lib/python3.6/site-packages/dnf/base.py", line 118, in _add_repo_to_sack
    repo.load()
  File "/usr/lib/python3.6/site-packages/dnf/repo.py", line 926, in load
    raise dnf.exceptions.RepoError(msg)
dnf.exceptions.RepoError: Failed to synchronize cache for repo 'updates'

Local variables in innermost frame:
dmsg: "Cannot download '%s': %s."
handle: <dnf.repo._Handle object at 0x7f2f211bd5f8>
tmpdir: '/tmp/dnf-kf7twm62'
msg: "Failed to synchronize cache for repo 'updates'"
self: <Repo updates>