State Sales Nexus CSV Checker Python Script Generator

import csv
from collections import defaultdict

THRESHOLD = 100000
WARN = THRESHOLD * 80 / 100.0

totals = defaultdict(float)
counts = defaultdict(int)

with open('sales_export.csv', newline='', encoding='utf-8-sig') as f:
    for row in csv.DictReader(f):
        state = (row.get('ship_to_state') or '').strip().upper()
        if not state:
            continue
        try:
            amount = float(str(row.get('net_amount', '0')).replace(',', ''))
        except ValueError:
            continue
        totals[state] += amount
        counts[state] += 1

print('State  Sales        Lines  Status')
for state in sorted(totals, key=totals.get, reverse=True):
    total = totals[state]
    if total >= THRESHOLD:
        status = 'OVER THRESHOLD'
    elif total >= WARN:
        status = 'WARNING'
    else:
        status = 'ok'
    print(state.ljust(6), format(total, ',.2f').rjust(12), str(counts[state]).rjust(6), ' ', status)

python nexus_check.py

# Export only the trailing 12 months of invoice lines.
# Net out credit memos so returns reduce the total.