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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 BuildApprovalSymlinksUrns(self, approval_id):
 """Builds list of symlinks URNs for the approval object."""

    return [
        self.ApprovalSymlinkUrnBuilder("cron", self.subject_urn.Basename(),
                                       self.token.username, approval_id)
    ]