undefined method `unified_mode'

[DivyaUppu]

When running with chef 14 I am getting this error, from this link it seems that unified_mode is not available in chef. Please help on this issue

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Recipe Compile Error in /var/chef/cache/cookbooks/line/resources/add_to_list.rb

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NoMethodError

---

undefined method `unified_mode' for #Class:0x0000000003fe41a8

Cookbook Trace:

---

/var/chef/cache/cookbooks/line/resources/add_to_list.rb:12:in `class_from_file'

Relevant File Content:

---

/var/chef/cache/cookbooks/line/resources/add_to_list.rb:

5: property :eol, String
6: property :ignore_missing, [true, false], default: true
7: property :path, String
8: property :pattern, [String, Regexp]
9:
10: resource_name :add_to_list
11: provides :add_to_list
12>> unified_mode true
13:
14: action :edit do
15: raise_not_found
16: sensitive_default
17: eol = default_eol
18: backup_if_true
19: current = target_current_lines
20:
21: # insert

System Info:

---

chef_version=14.11.21
platform=centos
platform_version=7.9.2009
ruby=ruby 2.5.3p105 (2018-10-18 revision 65156) [x86_64-linux]
program_name=/bin/chef-client
executable=/opt/chef/bin/chef-client