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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def version(self, pretty=False, best=False):
 """ Return the version of the OS distribution, as a string. For details, see :func:`distro.version`. """

        versions = [
            self.os_release_attr('version_id'),
            self.lsb_release_attr('release'),
            self.distro_release_attr('version_id'),
            self._parse_distro_release_content(
                self.os_release_attr('pretty_name')).get('version_id', ''),
            self._parse_distro_release_content(
                self.lsb_release_attr('description')).get('version_id', ''),
            self.uname_attr('release')
        ]
        version = ''
        if best:
            # This algorithm uses the last version in priority order that has
            # the best precision. If the versions are not in conflict, that
            # does not matter; otherwise, using the last one instead of the
            # first one might be considered a surprise.
            for v in versions:
                if v.count(".") > version.count(".") or version == '':
                    version = v
        else:
            for v in versions:
                if v != '':
                    version = v
                    break
        if pretty and version and self.codename():
            version = u'{0} ({1})'.format(version, self.codename())
        return version