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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 _parse_line(line):
 """ Convert one line from the extended log to dict. Args: line (str):
 Line which will be converted. Returns: dict: dict with ``timestamp``, ``command``, ``username`` and ``path`` \ keys. Note: Typical line looks like this:: /home/ftp/xex/asd bsd.dat, xex, STOR, 1398351777 Filename may contain ``,`` character, so I am ``rsplitting`` the line from the end to the beginning. """

    line, timestamp = line.rsplit(",", 1)
    line, command = line.rsplit(",", 1)
    path, username = line.rsplit(",", 1)

    return {
        "timestamp": timestamp.strip(),
        "command": command.strip(),
        "username": username.strip(),
        "path": path,
    }