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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 open(filename, mode="r", iline = 189, xline = 193, strict = True, ignore_geometry = False, endian = 'big'):
 """Open a segy file. Opens a segy file and tries to figure out its sorting, inline numbers, crossline numbers, and offsets, and enables reading and writing to this file in a simple manner. For reading, the access mode `r` is preferred. All write operations will raise an exception. For writing, the mode `r+` is preferred (as `rw` would truncate the file). Any mode with `w` will raise an error. The modes used are standard C file modes; please refer to that documentation for a complete reference. Open should be used together with python's ``with`` statement. Please refer to the examples. When the ``with`` statement is used the file will automatically be closed when the routine completes or an exception is raised. By default, segyio tries to open in ``strict`` mode. This means the file will be assumed to represent a geometry with consistent inline, crosslines and offsets. If strict is False, segyio will still try to establish a geometry, but it won't abort if it fails. When in non-strict mode is opened, geometry-dependent modes such as iline will raise an error. If ``ignore_geometry=True``, segyio will *not* try to build iline/xline or other geometry related structures, which leads to faster opens. This is essentially the same as using ``strict=False`` on a file that has no geometry. Parameters filename : str Path to file to open mode : {'r', 'r+'} File access mode, read-only ('r', default) or read-write ('r+') iline : int or segyio.TraceField Inline number field in the trace headers. Defaults to 189 as per the SEG-Y rev1 specification xline : int or segyio.TraceField Crossline number field in the trace headers. Defaults to 193 as per the SEG-Y rev1 specification strict : bool, optional Abort if a geometry cannot be inferred. Defaults to True. ignore_geometry : bool, optional Opt out on building geometry information, useful for e.g. shot organised files. Defaults to False. endian : {'big', 'msb', 'little', 'lsb'} File endianness, big/msb (default) or little/lsb Returns ------- file : segyio.SegyFile An open segyio file handle Raises ------ ValueError If the mode string contains 'w', as it would truncate the file Notes ----- .. versionadded:: 1.1 .. versionchanged:: 1.8 endian argument When a file is opened non-strict, only raw traces access is allowed, and using modes such as ``iline`` raise an error. Examples -------- Open a file in read-only mode: [1, 2, 3, 4, 5] Open a file in read-write mode: Open two files at once: Open a file little-endian file: """


    if 'w' in mode:
        problem = 'w in mode would truncate the file'
        solution = 'use r+ to open in read-write'
        raise ValueError(', '.join((problem, solution)))

    endians = {
        'little': 256, # (1 << 8)
        'lsb': 256,
        'big': 0,
        'msb': 0,
    }

    if endian not in endians:
        problem = 'unknown endianness {}, expected one of: '
        opts = ' '.join(endians.keys())
        raise ValueError(problem.format(endian) + opts)

    from . import _segyio
    fd = _segyio.segyiofd(str(filename), mode, endians[endian])
    fd.segyopen()
    metrics = fd.metrics()

    f = segyio.SegyFile(fd,
            filename = str(filename),
            mode = mode,
            iline = iline,
            xline = xline,
            endian = endian,
    )

    try:
        dt = segyio.tools.dt(f, fallback_dt = 4000.0) / 1000.0
        t0 = f.header[0][segyio.TraceField.DelayRecordingTime]
        samples = metrics['samplecount']
        f._samples = (numpy.arange(samples) * dt) + t0

    except:
        f.close()
        raise

    if ignore_geometry:
        return f

    return infer_geometry(f, metrics, iline, xline, strict)