old_contents: from sqlalchemy_utils import UUIDType
  
  from zou.app import db
  from zou.app.models.serializer import SerializerMixin
  from zou.app.models.base import BaseMixin
  
  
  class AttachmentFile(db.Model, BaseMixin, SerializerMixin):
      """
      Describes a file which is attached to a comment.
      """
  
      name = db.Column(db.String(250))
      size = db.Column(db.Integer(), default=1)
      extension = db.Column(db.String(6))
      mimetype = db.Column(db.String(255))
      comment_id = db.Column(
          UUIDType(binary=False), db.ForeignKey("comment.id"), index=True
      )
  
      __table_args__ = (
          db.UniqueConstraint("name", "comment_id", name="attachment_uc"),
      )
  
      def __repr__(self):
          return "<AttachmentFile %s>" % self.id
  
      def present(self):
          return {
              "id": str(self.id),
              "name": self.name,
              "extension": self.extension,
              "size": self.size,
          }
  
new_contents: from sqlalchemy_utils import UUIDType
  
  from zou.app import db
  from zou.app.models.serializer import SerializerMixin
  from zou.app.models.base import BaseMixin
  
  
  class AttachmentFile(db.Model, BaseMixin, SerializerMixin):
      """
      Describes a file which is attached to a comment.
      """
  
      name = db.Column(db.String(250))
      size = db.Column(db.Integer(), default=1)
      extension = db.Column(db.String(6))
      mimetype = db.Column(db.String(255))
      comment_id = db.Column(
          UUIDType(binary=False), db.ForeignKey("comment.id"), index=True
      )
  
      __table_args__ = (
          db.UniqueConstraint("name", "comment_id", name="attachment_uc"),
      )
  
      def __repr__(self):
          return "<AttachmentFile %s>" % self.id
  
      def present(self):
          return {
              "id": str(self.id),
              "name": self.name,
              "extension": self.extension,
              "size": self.size,
          }
  
      @classmethod
      def create_from_import(cls, data):
          data.pop("type", None)
          data.pop("comment", None)
          previous_data = cls.get(data["id"])
          if previous_data is None:
              return cls.create(**data)
          else:
              previous_data.update(data)
              return previous_data
  
  
subject: Fix import for attachment files