#318: helper.py, adjust incorrect typo
#318: helper.py, change 'list_to_check' -> 'list'
Merge pull request #320 from jeff1evesque/python_helper

#318: 'helper.py', adjust logic typos
Merge branch 'master' into python_data_validator
#318: helper.py, change 'index, value' -> 'key, value'
Merge pull request #321 from jeff1evesque/python_helper

#318: change 'index, value' -> 'key, value'
Merge branch 'master' into python_data_validator
#318: helper.py, use 'dict_duplicates[value].append(key)'
#318: helper.py, change '.iteritems():' -> '.items():'
Merge pull request #322 from jeff1evesque/python_helper

#318: properly remove non-duplicate elements
Merge branch 'master' into python_data_validator
#300: data_validator.py, remove duplicate JSON 'file upload' elements