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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 _unpack_from(buf, format_s, count=None, little_endian=True):
 """Read a binary format from the buffer."""


    if count is not None:
        assert count > 0
        format_s = '%i%s' % (count, format_s)

    if little_endian is True:
        format_s = '<' + format_s
    else:
        format_s = '>' + format_s

    size = struct.calcsize(format_s)
    res = struct.unpack_from(format_s, buf.read(size))

    if count is not None:
        return res
    else:
        return res[0]