I want to put an anchor tag into this ValidationError:

Customer.objects.get(email=value)if self.register:# this address is already registeredraise forms.ValidationError(_('An account already exists for this email address'))

The anchor tag would be <a href="some/url/to/login">Log in instead</a>

So, the error message when a user inputs an email that already exists would be something like:

'An account already exists for this email address. <a>Log in instead</a>?'

Thanks in advance!

This worked:

Customer.objects.get(email=value)if self.register:# this address is already registeredraise forms.ValidationError((_(mark_safe('An account already exists for this email address. <a href="#" class="email_error">Log in instead?</a>'))))

...but also needed this at the top of the Python file:

from django.utils.safestring import mark_safe