change

tools/cal_pos_neg.py

@@ -11,7 +11,7 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
-#!/usr/bin/python  
+#!/usr/bin/python   
 #-*- coding:utf-8 -*-   
 """
 docstring