diff --git a/Package/JavaScript/src/bellande_parser.js b/Package/JavaScript/src/bellande_parser.js
index c86feb1..1adb24a 100644
--- a/Package/JavaScript/src/bellande_parser.js
+++ b/Package/JavaScript/src/bellande_parser.js
@@ -1,45 +1,73 @@
+// Copyright (C) 2024 Bellande Algorithm Model Research Innovation Center, Ronaldson Bellande
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+
 const fs = require('fs');
 
 class BellandeFormat {
   parseBellande(filePath) {
     const content = fs.readFileSync(filePath, 'utf8');
     const lines = content.split('\n');
-    return this.parseLines(lines);
+    const parsedData = this.parseLines(lines);
+    return this.toStringRepresentation(parsedData);
   }
 
   parseLines(lines) {
     const result = {};
-    const stack = [[-1, result]];
+    let currentKey = null;
+    let currentList = null;
+    const indentStack = [[-1, result]];
 
     for (const line of lines) {
       const stripped = line.trim();
       if (!stripped || stripped.startsWith('#')) continue;
 
       const indent = line.length - line.trimLeft().length;
-      while (stack.length && indent <= stack[stack.length - 1][0]) {
-        stack.pop();
-      }
 
-      const parent = stack[stack.length - 1][1];
+      while (indentStack.length && indent <= indentStack[indentStack.length - 1][0]) {
+        const popped = indentStack.pop();
+        if (Array.isArray(popped[1])) {
+          currentList = null;
+        }
+      }
 
       if (stripped.includes(':')) {
         const [key, value] = stripped.split(':').map(s => s.trim());
+        currentKey = key;
         if (value) {
-          parent[key] = this.parseValue(value);
+          result[key] = this.parseValue(value);
         } else {
-          const newDict = {};
-          parent[key] = newDict;
-          stack.push([indent, newDict]);
+          result[key] = [];
+          currentList = result[key];
+          indentStack.push([indent, currentList]);
         }
       } else if (stripped.startsWith('-')) {
         const value = stripped.slice(1).trim();
-        if (Array.isArray(parent)) {
-          parent.push(this.parseValue(value));
+        const parsedValue = this.parseValue(value);
+        if (currentList !== null) {
+          currentList.push(parsedValue);
         } else {
-          const newList = [this.parseValue(value)];
-          const lastKey = Object.keys(parent).pop();
-          parent[lastKey] = newList;
-          stack.push([indent, newList]);
+          if (Object.keys(result).length === 0) {
+            result = [parsedValue];
+            currentList = result;
+            indentStack = [[-1, result]];
+          } else {
+            result[currentKey] = [parsedValue];
+            currentList = result[currentKey];
+            indentStack.push([indent, currentList]);
+          }
         }
       }
     }
@@ -57,9 +85,30 @@ class BellandeFormat {
     return value;
   }
 
+  toStringRepresentation(data) {
+    if (typeof data === 'object' && data !== null) {
+      if (Array.isArray(data)) {
+        const items = data.map(item => this.toStringRepresentation(item));
+        return '[' + items.join(', ') + ']';
+      } else {
+        const items = Object.entries(data).map(([k, v]) => `"${k}": ${this.toStringRepresentation(v)}`);
+        return '{' + items.join(', ') + '}';
+      }
+    } else if (typeof data === 'string') {
+      return `"${data}"`;
+    } else if (typeof data === 'number') {
+      return data.toString();
+    } else if (data === null) {
+      return 'null';
+    } else if (typeof data === 'boolean') {
+      return data.toString().toLowerCase();
+    } else {
+      return String(data);
+    }
+  }
+
   writeBellande(data, filePath) {
-    const content = this.toBellandeString(data);
-    fs.writeFileSync(filePath, content);
+    fs.writeFileSync(filePath, this.toBellandeString(data));
   }
 
   toBellandeString(data, indent = 0) {
@@ -84,14 +133,19 @@ class BellandeFormat {
 
   formatValue(value) {
     if (typeof value === 'string') {
-      return value.includes(' ') || value.includes(':') ? `"${value}"` : value;
+      if (value.includes(' ') || value.includes(':') || ['true', 'false', 'null'].includes(value.toLowerCase())) {
+        return `"${value}"`;
+      }
+      return value;
     }
     if (typeof value === 'boolean') {
-      return value.toString();
+      return value.toString().toLowerCase();
     }
     if (value === null) {
       return 'null';
     }
-    return value.toString();
+    return String(value);
   }
 }
+
+module.exports = BellandeFormat;
diff --git a/Package/Python/.gitignore b/Package/Python/.gitignore
index 3e54b1f..b111f4b 100644
--- a/Package/Python/.gitignore
+++ b/Package/Python/.gitignore
@@ -2,3 +2,4 @@ publish.sh
 tests
 setup.py
 dist
+src/bellande_format.egg-info
diff --git a/Package/Rust/README.md b/Package/Rust/README.md
new file mode 100644
index 0000000..e69de29
diff --git a/Package/Rust/src/bellande_parser.rs b/Package/Rust/src/bellande_parser.rs
new file mode 100644
index 0000000..c3fa077
--- /dev/null
+++ b/Package/Rust/src/bellande_parser.rs
@@ -0,0 +1,196 @@
+// Copyright (C) 2024 Bellande Algorithm Model Research Innovation Center, Ronaldson Bellande
+
+// This program is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// This program is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with this program.  If not, see <https://www.gnu.org/licenses/>.
+
+use std::collections::HashMap;
+use std::fs;
+use std::path::Path;
+
+#[derive(Debug, Clone)]
+enum BellandeValue {
+    String(String),
+    Integer(i64),
+    Float(f64),
+    Boolean(bool),
+    Null,
+    List(Vec<BellandeValue>),
+    Map(HashMap<String, BellandeValue>),
+}
+
+struct BellandeFormat;
+
+impl BellandeFormat {
+    pub fn parse_bellande<P: AsRef<Path>>(
+        &self,
+        file_path: P,
+    ) -> Result<BellandeValue, std::io::Error> {
+        let content = fs::read_to_string(file_path)?;
+        let lines: Vec<&str> = content.lines().collect();
+        let parsed_data = self.parse_lines(&lines);
+        Ok(parsed_data)
+    }
+
+    fn parse_lines(&self, lines: &[&str]) -> BellandeValue {
+        let mut result = HashMap::new();
+        let mut current_key = String::new();
+        let mut current_list: Option<Vec<BellandeValue>> = None;
+        let mut indent_stack = vec![(0, &mut result)];
+
+        for line in lines {
+            let stripped = line.trim();
+            if stripped.is_empty() || stripped.starts_with('#') {
+                continue;
+            }
+
+            let indent = line.len() - line.trim_start().len();
+
+            while indent_stack.last().map_or(false, |&(i, _)| indent <= i) {
+                indent_stack.pop();
+                current_list = None;
+            }
+
+            if let Some(colon_pos) = stripped.find(':') {
+                let (key, value) = stripped.split_at(colon_pos);
+                let key = key.trim().to_string();
+                let value = value[1..].trim();
+
+                current_key = key.clone();
+                if !value.is_empty() {
+                    let parsed_value = self.parse_value(value);
+                    indent_stack.last_mut().unwrap().1.insert(key, parsed_value);
+                } else {
+                    let new_list = Vec::new();
+                    indent_stack
+                        .last_mut()
+                        .unwrap()
+                        .1
+                        .insert(key, BellandeValue::List(new_list));
+                    if let BellandeValue::List(list) = indent_stack
+                        .last_mut()
+                        .unwrap()
+                        .1
+                        .get_mut(&current_key)
+                        .unwrap()
+                    {
+                        current_list = Some(list);
+                        indent_stack.push((indent, list));
+                    }
+                }
+            } else if stripped.starts_with('-') {
+                let value = stripped[1..].trim();
+                let parsed_value = self.parse_value(value);
+                if let Some(list) = &mut current_list {
+                    list.push(parsed_value);
+                } else {
+                    let mut new_list = Vec::new();
+                    new_list.push(parsed_value);
+                    indent_stack
+                        .last_mut()
+                        .unwrap()
+                        .1
+                        .insert(current_key.clone(), BellandeValue::List(new_list));
+                    if let BellandeValue::List(list) = indent_stack
+                        .last_mut()
+                        .unwrap()
+                        .1
+                        .get_mut(&current_key)
+                        .unwrap()
+                    {
+                        current_list = Some(list);
+                        indent_stack.push((indent, list));
+                    }
+                }
+            }
+        }
+
+        BellandeValue::Map(result)
+    }
+
+    fn parse_value(&self, value: &str) -> BellandeValue {
+        if value.eq_ignore_ascii_case("true") {
+            BellandeValue::Boolean(true)
+        } else if value.eq_ignore_ascii_case("false") {
+            BellandeValue::Boolean(false)
+        } else if value.eq_ignore_ascii_case("null") {
+            BellandeValue::Null
+        } else if value.starts_with('"') && value.ends_with('"') {
+            BellandeValue::String(value[1..value.len() - 1].to_string())
+        } else if let Ok(int_value) = value.parse::<i64>() {
+            BellandeValue::Integer(int_value)
+        } else if let Ok(float_value) = value.parse::<f64>() {
+            BellandeValue::Float(float_value)
+        } else {
+            BellandeValue::String(value.to_string())
+        }
+    }
+
+    pub fn write_bellande<P: AsRef<Path>>(
+        &self,
+        data: &BellandeValue,
+        file_path: P,
+    ) -> Result<(), std::io::Error> {
+        let content = self.to_bellande_string(data, 0);
+        fs::write(file_path, content)
+    }
+
+    fn to_bellande_string(&self, data: &BellandeValue, indent: usize) -> String {
+        match data {
+            BellandeValue::Map(map) => map
+                .iter()
+                .map(|(key, value)| {
+                    let value_str = match value {
+                        BellandeValue::Map(_) | BellandeValue::List(_) => {
+                            format!("\n{}", self.to_bellande_string(value, indent + 2))
+                        }
+                        _ => format!(" {}", self.format_value(value)),
+                    };
+                    format!("{}{}: {}", " ".repeat(indent), key, value_str)
+                })
+                .collect::<Vec<_>>()
+                .join("\n"),
+            BellandeValue::List(list) => list
+                .iter()
+                .map(|item| {
+                    format!(
+                        "{}- {}",
+                        " ".repeat(indent),
+                        self.to_bellande_string(item, indent + 2)
+                    )
+                })
+                .collect::<Vec<_>>()
+                .join("\n"),
+            _ => self.format_value(data),
+        }
+    }
+
+    fn format_value(&self, value: &BellandeValue) -> String {
+        match value {
+            BellandeValue::String(s) => {
+                if s.contains(' ')
+                    || s.contains(':')
+                    || ["true", "false", "null"].contains(&s.to_lowercase().as_str())
+                {
+                    format!("\"{}\"", s)
+                } else {
+                    s.clone()
+                }
+            }
+            BellandeValue::Integer(i) => i.to_string(),
+            BellandeValue::Float(f) => f.to_string(),
+            BellandeValue::Boolean(b) => b.to_string().to_lowercase(),
+            BellandeValue::Null => "null".to_string(),
+            BellandeValue::List(_) | BellandeValue::Map(_) => unreachable!(),
+        }
+    }
+}