Download fcc tower data in script rather than expecting it present

layers/fcc/towers/process.py

@@ -5,6 +5,7 @@ import csv
 import io
 import json
 import zipfile
+import urllib.request
 
 fieldnames = {
     "CO": ("Record Type", "Content Indicator", "File Number", "Registration Number", "Unique System Identifier",
@@ -15,8 +16,8 @@ fieldnames = {
 }
 filenames = ["CO", "EN", "HS", "RA", "RE", "SC"]
 files = {}
-
-with zipfile.ZipFile("r_tower.zip", "r") as z:
+resp = urllib.request.urlopen("https://data.fcc.gov/download/pub/uls/complete/r_tower.zip")
+with zipfile.ZipFile(io.BytesIO(resp.read())) as z:
     for filename in filenames:
         with z.open(f"{filename}.dat", "r") as f, io.TextIOWrapper( # Avoids `_csv.Error: iterator should return strings, not bytes (the file should be opened in text mode)`
             f, encoding="utf-8", newline="", errors="replace"