```ruby
class Repository < ActiveRecord::Base
  belongs_to :team
  belongs_to :created_by, foreign_key: :created_by_id, class_name: 'User'
  has_many :repository_columns
  has_many :repository_rows
  has_many :repository_table_states,
           inverse_of: :repository, dependent: :destroy

  auto_strip_attributes :name, nullify: false
  validates :name,
            presence: true,
            uniqueness: { scope: :team, case_sensitive: false },
            length: { maximum: Constants::NAME_MAX_LENGTH }
  validates :team, presence: true
  validates :created_by, presence: true
end
```

Implement 'copy' method on Repository object
user
```ruby
class Repository < ActiveRecord::Base
  belongs_to :team
  belongs_to :created_by, foreign_key: :created_by_id, class_name: 'User'
  has_many :repository_columns
  has_many :repository_rows
  has_many :repository_table_states,
           inverse_of: :repository, dependent: :destroy

  auto_strip_attributes :name, nullify: false
  validates :name,
            presence: true,
            uniqueness: { scope: :team, case_sensitive: false },
            length: { maximum: Constants::NAME_MAX_LENGTH }
  validates :team, presence: true
  validates :created_by, presence: true

  def copy(created_by, name)
    new_repo = nil

    begin
      Repository.transaction do
        # Clone the repository object
        new_repo = dup
        new_repo.created_by = created_by
        new_repo.name = name
        new_repo.save!

        # Clone columns (only if new_repo was saved)
        repository_columns.find_each do |col|
          new_col = col.dup
          new_col.repository = new_repo
          new_col.created_by = created_by
          new_col.save!
        end
      end
    rescue ActiveRecord::RecordInvalid
      return false
    end

    # If everything is okay, return new_repo
    new_repo
  end
end
```
assistant