<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def convert_cmd_scl(self, scl, cmd):
 """wrapping command in "scl enable" call and adds proper PATH """

        # load default SCL prefix to PATH
        prefix = self.policy.get_default_scl_prefix()
        # read prefix from /etc/scl/prefixes/${scl} and strip trailing '\n'
        try:
            prefix = open('/etc/scl/prefixes/%s' % scl, 'r').read()\
                     .rstrip('\n')
        except Exception as e:
            self._log_error("Failed to find prefix for SCL %s, using %s"
                            % (scl, prefix))

        # expand PATH by equivalent prefixes under the SCL tree
        path = os.environ["PATH"]
        for p in path.split(':'):
            path = '%s/%s%s:%s' % (prefix, scl, p, path)

        scl_cmd = "scl enable %s \"PATH=%s %s\"" % (scl, path, cmd)
        return scl_cmd