@spec create(
  Inttegro.Client.t(),
  Inttegro.Customers.CreateCustomerRequest.t(),
  keyword()
) ::
  {:ok, Inttegro.Customers.Customer.t()} | {:error, Exception.t()}

@spec lookup(
  Inttegro.Client.t(),
  Inttegro.Customers.LookupCustomerRequest.t(),
  keyword()
) ::
  {:ok, Inttegro.Customers.Customer.t()} | {:error, Exception.t()}

@spec page(
  Inttegro.Client.t(),
  Inttegro.Customers.PageCustomersRequest.t(),
  keyword()
) ::
  {:ok, Inttegro.Customers.CustomerPage.t()} | {:error, Exception.t()}

@spec update(
  Inttegro.Client.t(),
  Inttegro.Customers.UpdateCustomerRequest.t(),
  keyword()
) ::
  {:ok, Inttegro.Customers.Customer.t()} | {:error, Exception.t()}