Content-Type: multipart/mixed; boundary="1"

--1
Content-Type: multipart/mixed; boundary="2"

--2
Content-Type: message/rfc822

Content-Type: text/plain

1
--2
Content-Type: message/rfc822

Content-Type: text/plain

22
--1
Content-Type: message/rfc822

Content-Type: text/plain

333

---- EXPECTED STRUCTURE ----{
  "html_body": [],
  "text_body": [],
  "attachments": [
    2,
    3
  ],
  "parts": [
    {
      "headers_rfc": {
        "content_type": {
          "ContentType": {
            "c_type": "multipart",
            "c_subtype": "mixed",
            "attributes": {
              "boundary": "1"
            }
          }
        }
      },
      "headers_raw": [
        [
          {
            "Rfc": "content_type"
          },
          {
            "start": 13,
            "end": 44
          }
        ]
      ],
      "is_encoding_problem": false,
      "body": {
        "Multipart": [
          1
        ]
      },
      "offset_header": 0,
      "offset_body": 45,
      "offset_end": 283
    },
    {
      "headers_rfc": {
        "content_type": {
          "ContentType": {
            "c_type": "multipart",
            "c_subtype": "mixed",
            "attributes": {
              "boundary": "2"
            }
          }
        }
      },
      "headers_raw": [
        [
          {
            "Rfc": "content_type"
          },
          {
            "start": 62,
            "end": 93
          }
        ]
      ],
      "is_encoding_problem": false,
      "body": {
        "Multipart": [
          2,
          3
        ]
      },
      "offset_header": 49,
      "offset_body": 94,
      "offset_end": 283
    },
    {
      "headers_rfc": {
        "content_type": {
          "ContentType": {
            "c_type": "message",
            "c_subtype": "rfc822",
            "attributes": null
          }
        }
      },
      "headers_raw": [
        [
          {
            "Rfc": "content_type"
          },
          {
            "start": 111,
            "end": 127
          }
        ]
      ],
      "is_encoding_problem": false,
      "body": {
        "Message": {
          "html_body": [
            0
          ],
          "text_body": [
            0
          ],
          "attachments": [],
          "parts": [
            {
              "headers_rfc": {
                "content_type": {
                  "ContentType": {
                    "c_type": "text",
                    "c_subtype": "plain",
                    "attributes": null
                  }
                }
              },
              "is_encoding_problem": false,
              "body": {
                "Text": "1"
              },
              "offset_header": 128,
              "offset_body": 154,
              "offset_end": 156
            }
          ]
        }
      },
      "offset_header": 98,
      "offset_body": 128,
      "offset_end": 156
    },
    {
      "headers_rfc": {
        "content_type": {
          "ContentType": {
            "c_type": "message",
            "c_subtype": "rfc822",
            "attributes": null
          }
        }
      },
      "headers_raw": [
        [
          {
            "Rfc": "content_type"
          },
          {
            "start": 173,
            "end": 189
          }
        ]
      ],
      "is_encoding_problem": false,
      "body": {
        "Message": {
          "html_body": [],
          "text_body": [],
          "attachments": [
            0
          ],
          "parts": [
            {
              "headers_rfc": {
                "content_type": {
                  "ContentType": {
                    "c_type": "text",
                    "c_subtype": "plain",
                    "attributes": null
                  }
                }
              },
              "is_encoding_problem": true,
              "body": {
                "Text": "22\n--1\nContent-Type: message/rfc822\n\nContent-Type: text/plain\n\n333\n"
              },
              "offset_header": 190,
              "offset_body": 216,
              "offset_end": 280
            }
          ]
        }
      },
      "offset_header": 160,
      "offset_body": 190,
      "offset_end": 280
    }
  ]
}