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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 plate_exchanger_identifier(self):
        '''Method to create an identifying string in format 'L' + wavelength + 
        'A' + amplitude + 'B' + chevron angle-chevron angle. Wavelength and 
        amplitude are specified in units of mm and rounded to two decimal places.
        '''
        s = ('L' + str(round(self.wavelength*1000, 2))
             + 'A' + str(round(self.amplitude*1000, 2))
             + 'B' + '-'.join([str(i) for i in self.chevron_angles]))
        return s