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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def filter_users_by_email(email):
 """Return list of users by email address Typically one, at most just a few in length. First we look through EmailAddress table, than customisable User model table. Add results together avoiding SQL joins and deduplicate. """

    from .models import EmailAddress
    User = get_user_model()
    mails = EmailAddress.objects.filter(email__iexact=email)
    users = [e.user for e in mails.prefetch_related('user')]
    if app_settings.USER_MODEL_EMAIL_FIELD:
        q_dict = {app_settings.USER_MODEL_EMAIL_FIELD + '__iexact': email}
        users += list(User.objects.filter(**q_dict))
    return list(set(users))