[PYLINT FIX]pylint issue fixes (#348)
[PYLINT FIX]pylint issue fixes (#348)

Before Fix
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************* Module nnvm._base
R: 21, 0: Disallow trailing comma tuple (trailing-comma-tuple)
R: 27, 0: Disallow trailing comma tuple (trailing-comma-tuple)

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Your code has been rated at 9.99/

After Fix
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siju@siju-DAEMON:~/D/Community/nnvm$ make lint
pylint python/nnvm --rcfile=/media/siju/DATA/Community/nnvm/tests/lint/pylintrc

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Your code has been rated at 10.00/10 (previous run: 9.99/10, +0.01)
Laurawly/tvm-1,tqchen/tvm,Huyuwei/tvm,dmlc/tvm,Laurawly/tvm-1,Laurawly/tvm-1,Laurawly/tvm-1,dmlc/tvm,dmlc/tvm,tqchen/tvm,tqchen/tvm,Laurawly/tvm-1,Huyuwei/tvm,Huyuwei/tvm,tqchen/tvm,tqchen/tvm,dmlc/tvm,sxjscience/tvm,tqchen/tvm,tqchen/tvm,sxjscience/tvm,Laurawly/tvm-1,sxjscience/tvm,sxjscience/tvm,sxjscience/tvm,Huyuwei/tvm,tqchen/tvm,sxjscience/tvm,tqchen/tvm,sxjscience/tvm,Laurawly/tvm-1,tqchen/tvm,dmlc/tvm,Laurawly/tvm-1,Huyuwei/tvm,Laurawly/tvm-1,sxjscience/tvm,dmlc/tvm,dmlc/tvm,dmlc/tvm,Huyuwei/tvm,Huyuwei/tvm,sxjscience/tvm,Huyuwei/tvm,Laurawly/tvm-1,Huyuwei/tvm,dmlc/tvm