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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 iter_column(self, query=None, field="_id", **kwargs):
 """ Return one field as an iterator. Beware that if your query returns records where the field is not set, it will raise a KeyError. """

        find_kwargs = {
            "projection": {"_id": False}
        }
        find_kwargs["projection"][field] = True

        cursor = self._collection_with_options(kwargs).find(query, **find_kwargs)  # We only want 1 field: bypass the ORM

        patch_cursor(cursor, **kwargs)

        return (dotdict(x)[field] for x in cursor)