import os
text = """sample one rn sample two rn sample three"""
command = 'echo ' + text.strip() + '| clip'.
os.system(command)

sample one

sample two

sample three

import clipboard
clipboard.copy("line1nline2")  # now the clipboard content will be string "line1nline2"
clipboard.copy("line3") # add line3
text = clipboard.paste()  # text will have the content of clipboard

line = 'n'.join(line, new_line)
clipboard.copy(line)
text = clipboard.paste() # now all lines separated by newline will be on the clipboard.