Understanding PATCH syntax when constructing update requests

Updating this in case anyone else gets stuck fetching & changing datagroups with ansible. Playbook snippet comparing datagroup values and changing when necessary:

  - name: get data via REST api
    uri:
      url: "https://{{ inventory_hostname }}/mgmt/tm/ltm/dataGroup/internal/~Common~mtest-routing-datagroup"
      method: GET
      force_basic_auth: yes
      user: "{{ f5_admin_user }}"
      password: "{{ f5_admin_password }}"
      validate_certs: no
    register: result
    tags:
      - always

  - name: save current datagroup info
    set_fact:
      current_data="{{ result.json['records'][0]['data'] }}"
    tags:
      - always

  - name: Change data
    uri:
      url: "https://{{ inventory_hostname }}/mgmt/tm/ltm/dataGroup/internal/~Common~mtest-routing-datagroup"
      method: PATCH
      force_basic_auth: yes
      user: "{{ f5_admin_user }}"
      password: "{{ f5_admin_password }}"
      validate_certs: no
      body: {"records":[ {"name": "default", "data":"{{ desired_data }}"} ]}
      body_format: json
      status_code: 200
    when: not current_data == desired_data
    changed_when: not current_data == desired_data
    tags:
    - always