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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 ensure_unique_obs_ids_in_wide_data(obs_id_col, wide_data):
 """ Ensures that there is one observation per row in wide_data. Raises a helpful ValueError if otherwise. Parameters obs_id_col : str. Denotes the column in `wide_data` that contains the observation ID values for each row. wide_data : pandas dataframe. Contains one row for each observation. Should contain the specified `obs_id_col` column. Returns ------- None. """

    if len(wide_data[obs_id_col].unique()) != wide_data.shape[0]:
        msg = "The values in wide_data[obs_id_col] are not unique, "
        msg_2 = "but they need to be."
        raise ValueError(msg + msg_2)

    return None