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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 _compileSmsRegexes(self):
 """ Compiles regular expression used for parsing SMS messages based on current mode """

        if self._smsTextMode:
            if self.CMGR_SM_DELIVER_REGEX_TEXT == None:
                self.CMGR_SM_DELIVER_REGEX_TEXT = re.compile(r'^\+CMGR: "([^"]+)","([^"]+)",[^,]*,"([^"]+)"$')
                self.CMGR_SM_REPORT_REGEXT_TEXT = re.compile(r'^\+CMGR: ([^,]*),\d+,(\d+),"{0,1}([^"]*)"{0,1},\d*,"([^"]+)","([^"]+)",(\d+)$')
        elif self.CMGR_REGEX_PDU == None:
            self.CMGR_REGEX_PDU = re.compile(r'^\+CMGR: (\d*),"{0,1}([^"]*)"{0,1},(\d+)$')