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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 track(context, file_names):
 """Keep track of each file in list file_names. Tracking does not create or delete the actual file, it only tells the version control system whether to maintain versions (to keep track) of the file. """

    context.obj.find_repo_type()
    for fn in file_names:
        context.obj.call([context.obj.vc_name, 'add', fn])