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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 _build_url(self):
 """Build the URL for POSTing files."""

        self.connection["upload_url"] = (
            "%s/%s" % (self.connection["jss"].base_url, "dbfileupload"))
        self.connection["delete_url"] = (
            "%s/%s" % (self.connection["jss"].base_url,
                       "casperAdminSave.jxml"))