message: Updating BTreeMap::from to Rust 1.56 syntax
diff: use std::collections::BTreeMap;
  pub fn id_renames() -> BTreeMap<&'static str, &'static str> {
  - [
  + BTreeMap::from([
  ("fee_refund", "application_fee_refund"),
  ("invoiceitem", "invoice_item"),
  ("line_item", "invoice_line_item"),
  ("source_transaction", "charge"),
  ("item", "checkout_session_item"),
  - ]
  - .iter()
  - .copied()
  - .collect()
  + ])
  }
  pub type ObjectMap = BTreeMap<&'static str, &'static str>;
  #[rustfmt::skip]
  pub fn object_mappings() -> ObjectMap {
  - [
  + BTreeMap::from([
  // Config for object types
  ("account_business_profile", "business_profile"),
  ("account_capabilities_card_issuing", "capability_status"),
  @@ -179,10 +176,7 @@ pub fn object_mappings() -> ObjectMap {
  ("webhook_endpoint_api_version", "api_version"),
  ("create_webhook_endpoint_enabled_events", "event_filter"),
  ("update_webhook_endpoint_enabled_events", "event_filter"),
  - ]
  - .iter()
  - .copied()
  - .collect()
  + ])
  }
  pub type FieldMap = BTreeMap<FieldSpec, ImportSpec>;
  @@ -197,7 +191,7 @@ pub type ImportSpec = (
  #[rustfmt::skip]
  pub fn field_mappings() -> FieldMap {
  - [
  + BTreeMap::from([
  // Config for object types
  (("account", "type"), ("AccountType", "Option<AccountType>")),
  (("balance_transaction", "status"), ("BalanceTransactionStatus", "BalanceTransactionStatus")),
  @@ -546,8 +540,5 @@ pub fn field_mappings() -> FieldMap {
  ),
  (("transfer_schedule_params", "delay_days"), ("DelayDays", "Option<DelayDays>")),
  (("create_webhook_endpoint", "api_version"), ("ApiVersion", "Option<ApiVersion>")),
  - ]
  - .iter()
  - .copied()
  - .collect()
  + ])
  }
  