environment/lib/python2.7/site-packages/psutil/__init__.py
def disk_io_counters(perdisk=False):
    """Return system disk I/O statistics as a namedtuple including
    the following attributes:

     - read_count:  number of reads
     - write_count: number of writes
     - read_bytes:  number of bytes read
     - write_bytes: number of bytes written
     - read_time:   time spent reading from disk (in milliseconds)
     - write_time:  time spent writing to disk (in milliseconds)

    If perdisk is True return the same information for every
    physical disk installed on the system as a dictionary
    with partition names as the keys and the namedutuple
    described above as the values.
    """
    rawdict = _psplatform.disk_io_counters()
    if not rawdict:
        raise RuntimeError("couldn't find any physical disk")
    if perdisk:
        for disk, fields in rawdict.items():
            rawdict[disk] = _nt_disk_iostat(*fields)
        return rawdict
    else:
        return _nt_disk_iostat(*[sum(x) for x in zip(*rawdict.values())])
def disk_io_counters(perdisk=False):
    """Return system disk I/O statistics as a namedtuple including
    the following attributes:

     - read_count:  number of reads
     - write_count: number of writes
     - read_bytes:  number of bytes read
     - write_bytes: number of bytes written
     - read_time:   time spent reading from disk (in milliseconds)
     - write_time:  time spent writing to disk (in milliseconds)

    If perdisk is True return the same information for every
    physical disk installed on the system as a dictionary
    with partition names as the keys and the namedutuple
    described above as the values.
    """
    rawdict = _psplatform.disk_io_counters()
    if not rawdict:
        raise RuntimeError("couldn't find any physical disk")
    if perdisk:
        for disk, fields in rawdict.items():
            rawdict[disk] = _nt_disk_iostat(*fields)
        return rawdict
    else:
        return _nt_disk_iostat(*[sum(x) for x in zip(*rawdict.values())])
Return system disk I/O statistics as a namedtuple including
    the following attributes:

     - read_count:  number of reads
     - write_count: number of writes
     - read_bytes:  number of bytes read
     - write_bytes: number of bytes written
     - read_time:   time spent reading from disk (in milliseconds)
     - write_time:  time spent writing to disk (in milliseconds)

    If perdisk is True return the same information for every
    physical disk installed on the system as a dictionary
    with partition names as the keys and the namedutuple
    described above as the values.