json_schema: {
      "properties": {
          "author": {
              "type": "string"
          },
          "content_hash": {
              "type": "string"
          },
          "countries": {
              "items": {
                  "format": "country-code",
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "dates": {
              "items": {
                  "format": "date",
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "domains": {
              "items": {
                  "format": "hostname",
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "emails": {
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                  "format": "email",
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "extension": {
              "type": "string"
          },
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              "maxLength": 2048,
              "minLength": 1,
              "type": "string"
          },
          "foreign_id": {
              "type": "string"
          },
          "headers": {
              "type": [
                  "null",
                  "object"
              ]
          },
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                  "maxLength": 2048,
                  "minLength": 1,
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "languages": {
              "items": {
                  "format": "language-code",
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
          "mime_type": {
              "type": "string"
          },
          "parent": {
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                  "null",
                  "object"
              ]
          },
          "phone_numbers": {
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                  "minLength": 1,
                  "type": "string"
              },
              "type": "array",
              "_uniqueItems": true
          },
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              "minLength": 1,
              "type": "string"
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                  "format": "url",
                  "type": "string"
              },
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              "_uniqueItems": true
          }
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      "type": "object"
  }