def get_float_cell_value(cell_value) -> float:
    """Returns the value of an openpyxl cell value.

    This function is used in oder to operate with spreadsheets
    which use the comma as the decimal mark instead of a period.

    Arguments
    ----------
    * cell_value ~ The openpyxl cell value
    """
    if type(cell_value) not in (int, float):
        cell_value = cell_value.replace(",", ".")
        cell_value = float(cell_value)
    return cell_value