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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 _interpret_oserror(exc, cwd, cmd):
 """Interpret an OSError exc and raise the appropriate dbt exception. """

    if len(cmd) == 0:
        raise dbt.exceptions.CommandError(cwd, cmd)

    # all of these functions raise unconditionally
    if os.name == 'nt':
        _handle_windows_error(exc, cwd, cmd)
    else:
        _handle_posix_error(exc, cwd, cmd)

    # this should not be reachable, raise _something_ at least!
    raise dbt.exceptions.InternalException(
        'Unhandled exception in _interpret_oserror: {}'.format(exc)
    )