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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):
 """read the contents of the file that's been opened in read mode"""

        if 'r' == self._mode:
            return self._read_response.text
        elif 'rb' == self._mode:
            return self._read_response.content
        else:
            raise IOError("File not opened in read mode.")