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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 owner_search_fields(self):
 """ Returns all the fields that are CharFields except for password from the User model. For the built-in User model, that means username, first_name, last_name, and email. """

        try:
            from django.contrib.auth import get_user_model
        except ImportError:  # Django < 1.5
            from django.contrib.auth.models import User
        else:
            User = get_user_model()
        return [
            field.name for field in User._meta.fields
            if isinstance(field, models.CharField) and field.name != 'password'
        ]