def _supportsSymlinks(self):
        """
        Check for symlink support usable for Twisted's purposes.

        @return: C{True} if symlinks are supported on the current platform,
                 otherwise C{False}.
        @rtype: L{bool}
        """
        if self.isWindows():
            # We do the isWindows() check as newer Pythons support the symlink
            # support in Vista+, but only if you have some obscure permission
            # (SeCreateSymbolicLinkPrivilege), which can only be given on
            # platforms with msc.exe (so, Business/Enterprise editions).
            # This uncommon requirement makes the Twisted test suite test fail
            # in 99.99% of cases as general users don't have permission to do
            # it, even if there is "symlink support".
            return False
        else:
            # If we're not on Windows, check for existence of os.symlink.
            try:
                os.symlink
            except AttributeError:
                return False
            else:
                return True

        Check for symlink support usable for Twisted's purposes.

        @return: C{True} if symlinks are supported on the current platform,
                 otherwise C{False}.
        @rtype: L{bool}
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/python/runtime.py