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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(self, chunk_size=None):
 """ Return chunk_size of bytes, starting from self.pos, from self.content. """

        if chunk_size:
            data = self.content[self.pos:self.pos + chunk_size]
            self.pos += len(data)
            return data
        else:
            return self.content