p-append-file.py

import os
import sys
import time 
import prompt_toolkit

# Writes new & old text into buffer, renames buffer to original filename
def insert(originalfile,strings):
	with open(originalfile,'r') as f:
		with open('buffer.txt','w') as f2:
			for line in strings:
				f2.write(line + "\n\n")
				f2.write(f.read())
		os.rename('buffer.txt',originalfile)
		
		print("Done!\nFile: " + originalfile + " appended. ")
		time.sleep(1.0)

# User input
def main():
	with open(sys.argv[1]) as f:
		rawInput = f.readlines()
	print (rawInput)

	count = 0
	while True:
		
#		Allows pasting multi-line text	
		count += 1
		print (count)

# 		Prompt after path error: 
		if (count >= 2):
			print("Sorry couldn't find that filepath. ")

# 		Auto starts in user $home
		PATH = os.getenv("HOME") + "/"
		PATH = PATH + input("File to append to: ")

# 		Check path exists
		if(os.path.isfile(PATH) == True):
			count += 1
			break

	print(PATH)
	insert(PATH, rawInput)

if __name__ == "__main__":
	main()