```ruby
post[:amount] = amount(money)
```

* [method source](https://github.com/Shopify/active_merchant/blob/1e8658bc245e1524f4628fe80d76a19001ec1cdc/lib/active_merchant/billing/gateway.rb#L142-L160)
* [example](https://github.com/Shopify/active_merchant/blob/1e8658bc245e1524f4628fe80d76a19001ec1cdc/lib/active_merchant/billing/gateways/stripe.rb#L161)