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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_strings(self):
 """build call string for each device"""

        for idx, dev in enumerate(self.devices):
            header = 'system.' + dev
            self.gcalls[idx] = header + '.gcall(system.dae)\n'
            self.fcalls[idx] = header + '.fcall(system.dae)\n'
            self.gycalls[idx] = header + '.gycall(system.dae)\n'
            self.fxcalls[idx] = header + '.fxcall(system.dae)\n'
            self.jac0s[idx] = header + '.jac0(system.dae)\n'