Content-Type: multipart/mixed; boundary="1234567890123456789012345678901234567890123456789012345678901234567890123456789012"

--1234567890123456789012345678901234567890123456789012345678901234567890123456789012
Content-Type: multipart/mixed; boundary="123456789012345678901234567890123456789012345678901234567890123456789012345678901"

--123456789012345678901234567890123456789012345678901234567890123456789012345678901
Content-Type: multipart/mixed; boundary="12345678901234567890123456789012345678901234567890123456789012345678901234567890"

--12345678901234567890123456789012345678901234567890123456789012345678901234567890
Content-Type: text/plain

1
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Content-Type: text/plain

22
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Content-Type: text/plain

333
--12345678901234567890123456789012345678901234567890123456789012345678901234567890
Content-Type: text/plain

4444

---- EXPECTED STRUCTURE ----
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              "c_type": "multipart",
              "c_subtype": "mixed",
              "attributes": {
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    {
      "Text": {
        "headers": {
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                "c_subtype": "plain"
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            }
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        "is_html": false
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    },
    {
      "Text": {
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        "contents": "4444\n",
        "is_html": false
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}