How many Pidgeys you need to reach an XP (assuming you always evolve after 12 candies and not using lucky egg)

pidgey.py

import sys

if (len(sys.argv)<2):
	print "Usage: python pidgey.py targetxp"
	exit(0)

target_xp = int(sys.argv[1])

print "Target XP ", target_xp

total_pidgey = 0
current_pidgey = 0
current_pidgeotto = 0
current_candy = 0
current_xp = 0

while current_xp < target_xp:
	#catch current_pidgey, assume 100 points
	current_xp += 100
	total_pidgey += 1
	current_pidgey +=1
	current_candy += 3
	while (current_candy>12 and current_pidgey>0):
		current_pidgey -= 1
		current_pidgeotto += 1
		current_candy -= 12
		current_xp += 500 #assume not using lucky egg
	while (current_pidgeotto>12):
		current_pidgeotto -= 12 #exchange for candy
		current_candy += 12
	while (current_pidgey>12):
		current_pidgey -= 12 #exchange for candy
		current_candy += 12

		
print "Total pidgey needed ", total_pidgey
print "Current XP ", current_xp
print "Current pidgey ", current_pidgey