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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 groupby(self, by=None, axis=0, level=None, as_index=True, sort=True, group_keys=True, squeeze=False):
 """Returns a groupby on the schema rdd. This returns a GroupBy object. Note that grouping by a column name will be faster than most other options due to implementation."""

        from sparklingpandas.groupby import GroupBy
        return GroupBy(self, by=by, axis=axis, level=level, as_index=as_index,
                       sort=sort, group_keys=group_keys, squeeze=squeeze)