Getting an error when trying to retrieve the image stored in the database in my Ruby On Rails Application

I'm developing an online store application with rails.And in that i have included a paperclip gem to store images of the items.The image gets successfully stored to the database but when i'm trying to retrieve the image with it's show view i am getting an error saying that

> undefined method `image?' for #<Item:0x007f805b7a9d50>
Extracted source (around line #19):              

            <div>
                <% if @item.image? %>
                    <% image_tag @item.image.url%>
                    <br>
                <%end%>
            </div><br>

This is my code in the view to submit the image

       `<div>
            <%=f.label :image %>
            <%=f.file_field :image %><br><br>
        </div>
        <div>`

This is the migration file for the image storing on the table

`class AddImageToItems < ActiveRecord::Migration[5.0]
  def self.up
    add_column :items, :image_file_name, :string
    add_column :items, :image_content_type, :string
    add_column :items, :image_file_size, :integer
    add_column :items, :image_updated_at, :datetime
  end

  def self.down
    remove_column :items, :image_file_name
    remove_column :items, :image_content_type
    remove_column :items, :image_file_size
    remove_column :items, :image_updated_at
  end
end
`

This is the code for the show view

  `<div class="well">
        <h3> Item  :  <%= @item.title %>  </h3>
    </div>
    <div>
        <i>Quantity : </i><%= @item.qty %>
    </div>
    <div>
        <i>Price  : RS </i><%= @item.price %>
    </div><br>
    <div>
        <% if @item.image? %>
            <% image_tag @item.image.url%>
            <br>
        <%end%>
   </div>`

This is my show method on the items controller

def show @item =Item.find(params[:id]) end

Please help me to Solve this issue...