import requests

url = "https://{FUSION HOST}/api/collections/{collection}/schema/dynamicfields"

response = requests.get(url)

print(response.text)

[
  {
    "name": "<string>",
    "type": "<string>",
    "indexed": true,
    "stored": true,
    "multiValued": true,
    "required": true,
    "docValues": true,
    "omitNorms": true,
    "omitPositions": true,
    "omitTermFreqAndPositions": true,
    "termVectors": true,
    "termPositions": true,
    "termOffsets": true,
    "copyDests": [
      "<string>"
    ],
    "copySources": [
      "<string>"
    ],
    "numDocs": 123,
    "indexFields": [
      {
        "name": "<string>",
        "numDocs": 123
      }
    ],
    "default": "<string>"
  }
]