def delete_lines(self, count=None):
        count = count or 1
        top, bottom = self.margins
        line_offset = self.line_offset
        pt_cursor_position = self.pt_cursor_position

        # If cursor is outside scrolling margins it -- do nothin'.
        if top <= pt_cursor_position.y - line_offset <= bottom:
            data_buffer = self.data_buffer

            # Iterate from the cursor Y position until the end of the visible input.
            for line in range(pt_cursor_position.y - line_offset, bottom + 1):
                # When 'x' lines further are out of the margins, replace by an empty line,
                # Otherwise copy the line from there.
                if line + count > bottom:
                    data_buffer.pop(line + line_offset, None)
                else:
                    data_buffer[line + line_offset] = self.data_buffer[line + count + line_offset]
Deletes the indicated # of lines, starting at line with
dataset/ETHPy150Open jonathanslenders/pymux/pymux/screen.py/BetterScreen.delete_lines