age_column_mapper.py:74, in AgeColumnMapper.preview_column(self, df)
72 for _, column_contents in column.items():
73 pyphetools_age = self.map_cell(str(column_contents))
---> 74 preview_d[pyphetools_age.age_string] = column_contents
75 dlist = []
76 for k, v in preview_d.items():
AttributeError: 'str' object has no attribute 'age_string'