code: import stripe
  stripe.api_key = "sk_test_your_key"
  
  stripe.FileLink.modify(
    "link_1LSdch2eZvKYlo2ChSmmACpZ",
    metadata={"order_id": "6735"},
  )
  '''Response {
    "id": "link_1LSdch2eZvKYlo2ChSmmACpZ",
    "object": "file_link",
    "created": 1659517935,
    "expired": false,
    "expires_at": null,
    "file": "file_1JXy922eZvKYlo2CV17dW6tI",
    "livemode": false,
    "metadata": {},
    "url": "https://files.stripe.com/links/MDB8YWNjdF8xMDMyRDgyZVp2S1lsbzJDfGZsX3Rlc3RfSElFUVo0aE9oN3BxUjl3TE1BYWZqZ3lW00WFy5PY6L"
  }'''
nl: Update a file linkUpdates an existing file link object. Expired links can no longer be updated.Parameters expires_at optional A future timestamp after which the link will no longer be usable, or now to expire the link immediately. metadata optional dictionary Set of key-value pairs that you can attach to an object. This can be useful for storing additional information about the object in a structured format. Individual keys can be unset by posting an empty value to them. All keys can be unset by posting an empty value to metadata.ReturnsReturns the file link object if successful, and raises an error otherwise