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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 get_custom_field(self, field_name):
 """ Get a custom field object for this model field_name - Name of the custom field you want. """

        content_type = ContentType.objects.get_for_model(self)
        return CustomField.objects.get(
            content_type=content_type, name=field_name)