(De)-Serialize a Matrix fails in playground

[KappaDistributive]

(De)-Serialize a Matrix fails in rust-cookbook's playground with the following output:

   Compiling playground v0.0.1 (/playground)
error[E0277]: the trait bound `nalgebra::Matrix<i32, nalgebra::Dynamic, nalgebra::Dynamic, nalgebra::VecStorage<i32, nalgebra::Dynamic, nalgebra::Dynamic>>: serde::ser::Serialize` is not satisfied
    --> src/main.rs:11:51
     |
11   |     let serialized_matrix = serde_json::to_string(&matrix)?;
     |                                                   ^^^^^^^ the trait `serde::ser::Serialize` is not implemented for `nalgebra::Matrix<i32, nalgebra::Dynamic, nalgebra::Dynamic, nalgebra::VecStorage<i32, nalgebra::Dynamic, nalgebra::Dynamic>>`
     | 
    ::: /playground/.cargo/registry/src/github.com-1ecc6299db9ec823/serde_json-1.0.53/src/ser.rs:2224:17
     |
2224 |     T: ?Sized + Serialize,
     |                 --------- required by this bound in `serde_json::to_string`

error[E0277]: the trait bound `nalgebra::Matrix<i32, nalgebra::Dynamic, nalgebra::Dynamic, nalgebra::VecStorage<i32, nalgebra::Dynamic, nalgebra::Dynamic>>: serde::de::Deserialize<'_>` is not satisfied
    --> src/main.rs:14:45
     |
14   |     let deserialized_matrix: DMatrix<i32> = serde_json::from_str(&serialized_matrix)?;
     |                                             ^^^^^^^^^^^^^^^^^^^^ the trait `serde::de::Deserialize<'_>` is not implemented for `nalgebra::Matrix<i32, nalgebra::Dynamic, nalgebra::Dynamic, nalgebra::VecStorage<i32, nalgebra::Dynamic, nalgebra::Dynamic>>`
     | 
    ::: /playground/.cargo/registry/src/github.com-1ecc6299db9ec823/serde_json-1.0.53/src/de.rs:2397:8
     |
2397 |     T: de::Deserialize<'a>,
     |        ------------------- required by this bound in `serde_json::from_str`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0277`.
error: could not compile `playground`.

To learn more, run the command again with --verbose.

The same code, using the same Cargo.toml, works perfectly fine on my machine. Am not sure what's going on...?!