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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_shortstr(self):
 """Read a short string that's stored in up to 255 bytes. The encoding isn't specified in the AMQP spec, so assume it's utf-8 """

        self.bitcount = self.bits = 0
        slen = unpack('B', self.input.read(1))[0]
        return self.input.read(slen).decode('utf-8')