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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 check_num_columns_in_param_list_arrays(param_list):
 """ Ensure that each array in param_list, that is not None, has the same number of columns. Raises a helpful ValueError if otherwise. Parameters param_list : list of ndarrays or None. Returns ------- None. """

    try:
        num_columns = param_list[0].shape[1]
        assert all([x is None or (x.shape[1] == num_columns)
                    for x in param_list])
    except AssertionError:
        msg = "param_list arrays should have equal number of columns."
        raise ValueError(msg)

    return None