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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 insert(self, loc, column, value, allow_duplicates=False):
 """ Insert column into DataFrame at specified location. Raises a ValueError if `column` is already contained in the DataFrame, unless `allow_duplicates` is set to True. Parameters loc : int Insertion index. Must verify 0 <= loc <= len(columns) column : string, number, or hashable object label of the inserted column value : int, Series, or array-like allow_duplicates : bool, optional """

        self._ensure_valid_index(value)
        value = self._sanitize_column(column, value, broadcast=False)
        self._data.insert(loc, column, value,
                          allow_duplicates=allow_duplicates)