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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, file_des, num_bytes):
 """Read number of bytes from a file descriptor, returns bytes read. Args: file_des: An integer file descriptor for the file object requested. num_bytes: Number of bytes to read from file. Returns: Bytes read from file. Raises: OSError: bad file descriptor. TypeError: if file descriptor is not an integer. """

        file_handle = self.filesystem.get_open_file(file_des)
        file_handle.raw_io = True
        return file_handle.read(num_bytes)