UserSerDe.rs

#[derive(Deserialize, Serialize)]
struct User {
    customer_id: String,
    senior_citizen: i32,
    #[serde(default, rename = "churnProbability")]
    churn_probability: Option<f64>,
    #[serde(rename = "MonthlyCharges")]
    monthly_charges: f64,
    #[serde(rename = "TotalCharges")]
    total_charges: f64,
    is_male: i32,
    is_partner: i32,
    payment_method: i32,
    // [...] other attributes
}

// Usage example. Let's say we've a serialized JSON in a serialized_user variable, then deserialization is as simple as
let mut user: User = serde_json::from_str(&serialized_user)?;

Maybe a usage example would be helpful.
Also we can omit some of the i32 and f64 fields that doesn't have special usage.

done