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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 _get_subplot_number(subplot_val):
 """ Extract the subplot number from a subplot value string. 'x3' -> 3 'polar2' -> 2 'scene' -> 1 'y' -> 1 Note: the absence of a subplot number (e.g. 'y') is treated by plotly as a subplot number of 1 Parameters subplot_val: str Subplot string value (e.g. 'scene4') Returns ------- int """

    match = _subplot_re.match(subplot_val)
    if match:
        subplot_number = int(match.group(1))
    else:
        subplot_number = 1
    return subplot_number