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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 get_hnd(self, cache_id_obj, section=None, method=None):
 """Gets a handle for the given cache file with exclusive access. The handle is meant to be used in a resource block. Parameters cache_id_obj : object An object uniquely identifying the cached resource. Note that some methods require the cache id object to be json serializable. The string representation of each element, however, has to reflect its content in a lossless way. method : string (optional; default=None) Defines the method used to encode the cached content. If None the default method of this cache is used. The method must be consistent between multiple accesses of the same cache resource. """

        cache_file = self.get_file(cache_id_obj, section)
        if cache_file not in self._locks:
            try:
                while not self._own.acquire(True):
                    pass
                if cache_file not in self._locks:
                    if method is None:
                        m = self._method
                    else:
                        m = methods.get(method, None)
                    if m is None:
                        raise ValueError(
                            "unknown method: '{0}'".format(method))
                    res = _CacheLock(cache_file, cache_id_obj, self._full_base,
                                     self._quota, self._ram_quota,
                                     self._warnings, self.verbose, m)
                    self._locks[cache_file] = res
                else:
                    res = None
            finally:
                self._own.release()
        else:
            res = None
        if res is None:
            res = self._locks[cache_file]
            res.ensure_cache_id(cache_id_obj)
        self.enforce_ram_quota()
        return res