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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 getSignalHeaders(self):
 """ Returns the header of all signals as array of dicts Parameters None """

        signalHeader = []
        for chn in np.arange(self.signals_in_file):
            signalHeader.append(self.getSignalHeader(chn))
        return signalHeader