'Inserts the indicated # of lines at line with cursor. Lines
displayed **at** and below the cursor move down. Lines moved
past the bottom margin are lost.
:param count: number of lines to delete.'

def insert_lines(self, count=None):

    count = (count or 1)
    (top, bottom) = self.margins
    if (top <= self.cursor.y <= bottom):
        for line in range(self.cursor.y, min((bottom + 1), (self.cursor.y + count))):
            self.buffer.pop(bottom)
            self.buffer.insert(line, take(self.columns, self.default_line))
        self.carriage_return()
