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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 _list_files_in_path(path, pattern="*.stan"):
 """ indexes a directory of stan files returns as dictionary containing contents of files """


    results = []
    for dirname, subdirs, files in os.walk(path):
        for name in files:
            if fnmatch(name, pattern):
                results.append(os.path.join(dirname, name))
    return(results)