do not run forms code during migration

database does not exist yet

apps/transactions/forms.py

@@ -1,4 +1,5 @@
 from django import forms  
+import sys
 import datetime
 from apps.transactions.models import Transaction
 from apps.rates.models import ExchangeRate
@@ -16,6 +17,8 @@ class TransactionForm(forms.ModelForm):
         model = Transaction
         fields = "__all__"
 
+        # do not run this code in initial migration, because the database has not been built yet
+        if not "migrate" in sys.argv:
             exchangerates = ExchangeRate.objects.filter(datetime_valid__gt = datetime.datetime.today() - datetime.timedelta(days=7))
             crypto_currencies = [(x, x) for x in sorted({ex.crypto_currency for ex in exchangerates})]
             fiat_currencies = [(x, x) for x in sorted({ex.fiat_currency for ex in exchangerates})]
@@ -25,7 +28,6 @@ class TransactionForm(forms.ModelForm):
                 'crypto_currency': forms.Select(choices = crypto_currencies),
             }
 
-
 class ImportForm(forms.Form):
     api_key = forms.CharField(label='API Key', widget=forms.PasswordInput, max_length=100)
     api_secret = forms.CharField(label='API Secret', widget=forms.PasswordInput, max_length=100)