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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 read_inputs(self):
 """ Read risk data and sources if any """

        oq = self.oqparam
        self._read_risk_data()
        self.check_overflow()  # check if self.sitecol is too large
        if ('source_model_logic_tree' in oq.inputs and
                oq.hazard_calculation_id is None):
            self.csm = readinput.get_composite_source_model(
                oq, self.monitor(), srcfilter=self.src_filter)
        self.init()