stop using 'with open()' to handle files (#590)
stop using 'with open()' to handle files (#590)

* not use with open() to handle files
objmagic/heron,wangli1426/heron,srkukarni/heron,streamlio/heron,tomncooper/heron,moomou/heron,cliffyg/heron,lewiskan/heron,moomou/heron,zhangzhonglai/heron,ashvina/heron,ashvina/heron,moomou/heron,streamlio/heron,streamlio/heron,moomou/heron,lukess/heron,streamlio/heron,cliffyg/heron,tomncooper/heron,cs564/heron,billonahill/heron,nlu90/heron,billonahill/heron,objmagic/heron,streamlio/heron,srkukarni/heron,mycFelix/heron,objmagic/heron,huijunwu/heron,lukess/heron,tomncooper/heron,huijunwu/heron,cs564/heron,twitter/heron,streamlio/heron,twitter/heron,objmagic/heron,lewiskan/heron,nlu90/heron,ashvina/heron,cliffyg/heron,streamlio/heron,lucperkins/heron,zhangzhonglai/heron,mycFelix/heron,tomncooper/heron,cliffyg/heron,cliffyg/heron,lukess/heron,lukess/heron,cs564/heron,ashvina/heron,tomncooper/heron,lewiskan/heron,zhangzhonglai/heron,huijunwu/heron,twitter/heron,huijunwu/heron,streamlio/heron,moomou/heron,nlu90/heron,huijunwu/heron,cs564/heron,lukess/heron,wangli1426/heron,ashvina/heron,nlu90/heron,moomou/heron,wangli1426/heron,cliffyg/heron,ashvina/heron,lukess/heron,lewiskan/heron,srkukarni/heron,ashvina/heron,lucperkins/heron,tomncooper/heron,billonahill/heron,twitter/heron,nlu90/heron,moomou/heron,huijunwu/heron,mycFelix/heron,moomou/heron,nlu90/heron,mycFelix/heron,lewiskan/heron,lucperkins/heron,cliffyg/heron,huijunwu/heron,twitter/heron,lucperkins/heron,zhangzhonglai/heron,nlu90/heron,ashvina/heron,lucperkins/heron,lucperkins/heron,objmagic/heron,lucperkins/heron,billonahill/heron,lucperkins/heron,nlu90/heron,huijunwu/heron,zhangzhonglai/heron,srkukarni/heron,cs564/heron,tomncooper/heron,zhangzhonglai/heron,billonahill/heron,cs564/heron,srkukarni/heron,mycFelix/heron,lukess/heron,twitter/heron,billonahill/heron,tomncooper/heron,cs564/heron,mycFelix/heron,lukess/heron,srkukarni/heron,billonahill/heron,lewiskan/heron,zhangzhonglai/heron,cliffyg/heron,srkukarni/heron,srkukarni/heron,objmagic/heron,wangli1426/heron,wangli1426/heron,objmagic/heron,zhangzhonglai/heron,lewiskan/heron,billonahill/heron,wangli1426/heron,moomou/heron,wangli1426/heron,wangli1426/heron,mycFelix/heron,objmagic/heron,wangli1426/heron,lukess/heron,nlu90/heron,zhangzhonglai/heron,lewiskan/heron,mycFelix/heron,twitter/heron,cs564/heron,twitter/heron,streamlio/heron,cs564/heron,mycFelix/heron,lewiskan/heron,cliffyg/heron,ashvina/heron,objmagic/heron,tomncooper/heron,billonahill/heron