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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 getChangeSets(self):
 """Get all the ChangeSets of this workitem :return: a :class:`list` contains all the :class:`rtcclient.models.ChangeSet` objects :rtype: list """


        changeset_tag = ("rtc_cm:com.ibm.team.filesystem.workitems."
                         "change_set.com.ibm.team.scm.ChangeSet")
        return (self.rtc_obj
                    ._get_paged_resources("ChangeSet",
                                          workitem_id=self.identifier,
                                          customized_attr=changeset_tag,
                                          page_size="10"))