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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_next_into_buf(self):
 """Read data from the file in self.bufsize chunks until we're certain we have a full line in the buffer. """

        file_pos = self.fileobject.tell()
        if (file_pos == 0) and (self.buf == b''):
            raise StopIteration
        while file_pos and (self.get_start_of_line() == 0):
            bytes_to_read = min(self.bufsize, file_pos)
            file_pos = file_pos - bytes_to_read
            self.fileobject.seek(file_pos)
            new_stuff = self.fileobject.read(bytes_to_read)[:bytes_to_read]
            self.fileobject.seek(file_pos)
            self.buf = new_stuff + self.buf