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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_column_existence(col_name, df, presence=True):
 """ Checks whether or not `col_name` is in `df` and raises a helpful error msg if the desired condition is not met. Parameters col_name : str. Should represent a column whose presence in `df` is to be checked. df : pandas DataFrame. The dataframe that will be checked for the presence of `col_name`. presence : bool, optional. If True, then this function checks for the PRESENCE of `col_name` from `df`. If False, then this function checks for the ABSENCE of `col_name` in `df`. Default == True. Returns ------- None. """

    if presence:
        if col_name not in df.columns:
            msg = "Ensure that `{}` is in `df.columns`."
            raise ValueError(msg.format(col_name))
    else:
        if col_name in df.columns:
            msg = "Ensure that `{}` is not in `df.columns`."
            raise ValueError(msg.format(col_name))
    return None