How to retrieve a Contact linked to an Opportunity via REST API?

{
  "id": "aec8b61c-48b0-11ed-9a88-02d60046d9de",
  "name": "Michael Test Deal 2",
  "date_entered": "2022-10-10T15:32:00+00:00",
  "date_modified": "2022-10-12T14:22:14+00:00",
  "modified_user_id": "1",
  "modified_by_name": "Jen Smith",
  "modified_user_link": {
    "full_name": "Jen Smith",
    "id": "1",
    "_acl": {
      "fields": {
        "pwd_last_changed": {
          "write": "no",
          "create": "no"
        },
        "last_login": {
          "write": "no",
          "create": "no"
        }
      },
      "_hash": "6d408abe1708e7afd72eaecf780699c2"
    }
  },
  "created_by": "1",
  "created_by_name": "Jen Smith",
  "created_by_link": {
    "full_name": "Jen Smith",
    "id": "1",
    "_acl": {
      "fields": {
        "pwd_last_changed": {
          "write": "no",
          "create": "no"
        },
        "last_login": {
          "write": "no",
          "create": "no"
        }
      },
      "_hash": "6d408abe1708e7afd72eaecf780699c2"
    }
  },
  "description": "Description",
  "deleted": false,
  "opportunity_type": "",
  "account_name": "SugarCRM EndCustomer",
  "accounts": {
    "name": "SugarCRM EndCustomer",
    "id": "e96d6afe-432b-11ed-bdc3-02d60046d9de",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "account_id": "e96d6afe-432b-11ed-bdc3-02d60046d9de",
  "campaign_id": "",
  "campaign_name": "",
  "campaign_opportunities": {
    "name": "",
    "id": "",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "lead_source": "",
  "amount": "4521.000000",
  "amount_usdollar": "4521.000000",
  "date_closed": "2022-10-27",
  "date_closed_timestamp": 0,
  "next_step": "",
  "sales_stage": "Needs Analysis",
  "sales_status": "In Progress",
  "probability": 25,
  "best_case": "0.000000",
  "worst_case": "0.000000",
  "commit_stage": "exclude",
  "forecasted_likely": "0.000000",
  "lost": "0.000000",
  "commit_stage_cascade": "",
  "closed_won_revenue_line_items": 0,
  "service_start_date": "",
  "service_open_revenue_line_items": 0,
  "service_start_date_cascade": "",
  "total_revenue_line_items": 0,
  "closed_revenue_line_items": 0,
  "included_revenue_line_items": 0,
  "renewal_parent_id": "",
  "renewal_parent_name": "",
  "renewal_parent": {
    "name": "",
    "id": "",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "widget_sales_stage": "",
  "widget_date_closed": "",
  "widget_amount": "",
  "sales_stage_cascade": "",
  "date_closed_cascade": "",
  "contact_role": "",
  "service_duration_value": null,
  "service_duration_unit": "",
  "service_duration_value_cascade": null,
  "service_duration_unit_cascade": "",
  "service_open_flex_duration_rlis": 0,
  "mkto_sync": false,
  "mkto_id": null,
  "renewal": false,
  "ai_opp_conv_score_enum": "",
  "following": true,
  "my_favorite": false,
  "tag": [],
  "locked_fields": [],
  "sync_key": "",
  "assigned_user_id": "",
  "assigned_user_name": "",
  "assigned_user_link": {
    "full_name": "",
    "id": "",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "team_count": "",
  "team_count_link": {
    "team_count": "",
    "id": "1",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "team_name": [
    {
      "id": "1",
      "name": "Global",
      "name_2": "",
      "primary": true,
      "selected": false
    }
  ],
  "currency_id": "-99",
  "base_rate": "1.000000",
  "currency_name": "",
  "currencies": {
    "name": "",
    "id": "-99",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    },
    "symbol": ""
  },
  "currency_symbol": "",
  "is_escalated": false,
  "dri_workflow_template_id": "",
  "dri_workflow_template_name": "",
  "dri_workflow_template_link": {
    "name": "",
    "id": "",
    "_acl": {
      "fields": [],
      "_hash": "654d337e0e912edaa00dbb0fb3dc3c17"
    }
  },
  "zift_deal_id_c": "8a98828483b17b1e0183c2857d974147",
  "zift_deal_partner_c": "Test sugar 4",
  "zift_deal_contact_c": "Test Sugar4",
  "zift_registered_deal_c": true,
  "zift_deal_approval_status_c": "PENDING",
  "zift_distributed_deal_c": false,
  "testsinglecheckbox_c": true,
  "testmultiselect_c": [
    "Value2",
    "Value3"
  ],
  "test_radio_deal_field_c": "Value3",
  "test_date_deal_field_c": "2022-10-10",
  "test_select_deal_field_c": "Value2",
  "zift_deal_cosell_partner_c": "",
  "account_id1_c": "",
  "account_id_c": "6699c47a-2480-11ed-b24b-02d60046d9de",
  "contact_id_c": "9e30aae8-2480-11ed-a8b7-063b0cd98a86",
  "_acl": {
    "fields": []
  },
  "_module": "Opportunities"
}