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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_utf(self, offset, len):
 """Reads a UTF-8 string of a given length from the packet"""

        try:
            result = self.data[offset:offset + len].decode('utf-8')
        except UnicodeDecodeError:
            result = str('')
        return result