Redmine

How to solve that error.

logfile..
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Started GET "/redmine/projects/ph/import_issues" for 127.0.0.1 at 2015-08-20 14:45:15 +0530
Processing by ImportIssuesController#index as HTML
Parameters: {"project_id"=>"ph"}
Current user: redmine_eng1 (id=6)
Completed 500 Internal Server Error in 136.0ms

NoMethodError (undefined method `load_templates' for #<Class:0x3e7f840>):
activerecord (3.2.22) lib/active_record/dynamic_matchers.rb:55:in `method_missing'
plugins/redmine_import_issues/app/controllers/import_issues_controller.rb:34:in `index'
actionpack (3.2.22) lib/action_controller/metal/implicit_render.rb:4:in `send_action'
actionpack (3.2.22) lib/abstract_controller/base.rb:167:in `process_action'
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controller file.
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class ImportIssuesController < ApplicationController
unloadable

before_filter :find_project_by_project_id
  before_filter :authorize

helper :custom_fields
  include CustomFieldsHelper  
  helper :attachments
  include AttachmentsHelper
  include TimelogHelper

def index
    @import = ImportAction.new
    @trackers = @project.trackers
    @templates = ImportAction.load_templates(@project)
    @in_progress = [] # ImportAction.load_in_progress
  end

def create
    if params[:attachments].present?
      @import = ImportAction.new(params[:import])
      @import.project = @project
      @import.user = User.current
      @import.save_attachments(params[:attachments])
      @import.save

if @import.check_file      
        redirect_to prepare_project_import_issue_path(@project, @import)
      else
        flash[:error] = l(:error_file_incorrect)
        redirect_to project_import_issues_path(@project)
      end
    else
      flash[:error] = l(:error_file_mandatory)
      redirect_to project_import_issues_path(@project)
    end    
  end
end

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model file..

def self.load_templates(project)
    ImportAction.where(:is_template => true, :project_id => project)
  end

def self.load_in_progress
    ImportAction.where(:status => 'in_progress')
  end