Get E621 Species Siblings

#!/usr/bin/env python3

import requests
import time

# set these!
USERNAME = "" # e621 username
API_KEY = "" # e621 api key
# you need to enable API access to get a key.
# to enable API access, you must go to your e621 API page (Account > Manage API Access) and generate an API key.

pages = 400




# setting up variables for POST request
url = "https://e621.net/tags.json"
headers = {'user-agent': 'tagSpecies/' + USERNAME}
auth = requests.auth.HTTPBasicAuth(USERNAME, API_KEY)

for i in range(1, pages+1, 1):
    r = requests.get(url, params = {"search[category]": "5", "limit": "1000", "search[order]": "count", "page": i}, headers=headers, auth=auth)

    # stop searches if we get any code back other than 200 (OK)
    if (r.status_code != 200):
        print("ERR:", r.status_code)
        exit

    f = open("species.txt", 'a')
    for curTag in r.json():
        FileLine = curTag['name'] + "\n" + "species:" + curTag['name'] + "\n\n"
        f.write(FileLine)
        ConsoleLine = curTag['name'] + " -> " + "species:" + curTag['name']
        print(ConsoleLine)

    f.close()