Cargo Features

imdb-id has no features set by default.

[dependencies]
imdb-id = { version = "3.0.7", features = ["yaml"] }
yaml = serde_yaml

Features from optional dependencies

In crates that don't use the dep: syntax, optional dependencies automatically become Cargo features. These features may have been created by mistake, and this functionality may be removed in the future.

serde_yaml yaml?

Enables serde_yaml

https://rustsec.org/advisories/RUSTSEC-2018-0005.html