python remove lines of string

output_String = input_String.split("\n", 1)[1]
#this will get rid of the first line and keep the rest
output_String = input_String.split("\n", 3)[1]
# this will get rid of the first 3 lines ecept the 2nd line and keep everything else
output_String = input_String.split("\n", 4)[0]
# this will get rid of the first 4 lines ecept the first and keep any lines after the 4th line if there are any