diff --git a/nac3core/src/type_check/signature.rs b/nac3core/src/type_check/signature.rs
index 7b26e827f3..b1e35db0d6 100644
--- a/nac3core/src/type_check/signature.rs
+++ b/nac3core/src/type_check/signature.rs
@@ -2,7 +2,9 @@
 use super::context::TopLevelContext;
 use super::primitives::*;
 use super::typedef::*;
-use rustpython_parser::ast::{ExpressionType, Statement, StatementType, StringGroup, ComprehensionKind};
+use rustpython_parser::ast::{
+    ComprehensionKind, ExpressionType, Statement, StatementType, StringGroup,
+};
 use std::collections::HashMap;
 
 // TODO: fix condition checking, return error message instead of panic...
@@ -49,10 +51,7 @@ fn name_from_expr<'a>(expr: &'a ExpressionType) -> &'a str {
     }
 }
 
-fn type_from_expr<'a>(
-    ctx: &'a TopLevelContext,
-    expr: &'a ExpressionType,
-) -> Result<Type, String> {
+fn type_from_expr<'a>(ctx: &'a TopLevelContext, expr: &'a ExpressionType) -> Result<Type, String> {
     match expr {
         ExpressionType::Identifier { name } => {
             ctx.get_type(name).ok_or_else(|| "no such type".into())
@@ -161,7 +160,11 @@ fn resolve_function<'a>(
     }
 }
 
-fn get_expression_unknowns<'a>(defined: &mut Vec<&'a str>, unknowns: &mut Vec<&'a str>, expr: &'a ExpressionType) {
+fn get_expression_unknowns<'a>(
+    defined: &[&'a str],
+    unknowns: &mut Vec<&'a str>,
+    expr: &'a ExpressionType,
+) {
     match expr {
         ExpressionType::BoolOp { values, .. } => {
             for v in values.iter() {
@@ -209,16 +212,16 @@ fn get_expression_unknowns<'a>(defined: &mut Vec<&'a str>, unknowns: &mut Vec<&'
             }
             let g = &generators[0];
             get_expression_unknowns(defined, unknowns, &g.iter.node);
-            let mut scoped = defined.clone();
+            let mut scoped = defined.to_owned();
             get_expression_unknowns(defined, &mut scoped, &g.target.node);
             for if_expr in g.ifs.iter() {
-                get_expression_unknowns(&mut scoped, unknowns, &if_expr.node);
+                get_expression_unknowns(&scoped, unknowns, &if_expr.node);
             }
             match kind.as_ref() {
                 ComprehensionKind::List { element } => {
-                    get_expression_unknowns(&mut scoped, unknowns, &element.node);
+                    get_expression_unknowns(&scoped, unknowns, &element.node);
                 }
-                _ => unimplemented!()
+                _ => unimplemented!(),
             }
         }
         ExpressionType::Slice { elements } => {
@@ -236,10 +239,95 @@ fn get_expression_unknowns<'a>(defined: &mut Vec<&'a str>, unknowns: &mut Vec<&'
             get_expression_unknowns(defined, unknowns, &body.node);
             get_expression_unknowns(defined, unknowns, &orelse.node);
         }
-        _ => ()
+        _ => (),
     };
 }
 
+pub fn get_pattern_match_unknowns<'a>(
+    defined: &mut Vec<&'a str>,
+    unknowns: &mut Vec<&'a str>,
+    expr: &'a ExpressionType,
+) {
+    match expr {
+        ExpressionType::Identifier { name } => {
+            defined.push(&name.as_str());
+        }
+        ExpressionType::Tuple { elements } => {
+            for v in elements.iter() {
+                get_pattern_match_unknowns(defined, unknowns, &v.node);
+            }
+        }
+        _ => {
+            get_expression_unknowns(defined, unknowns, expr);
+        }
+    }
+}
+
+pub fn get_statement_unknowns<'a>(
+    defined: &mut Vec<&'a str>,
+    unknowns: &mut Vec<&'a str>,
+    stmts: &'a [Statement],
+) {
+    for stmt in stmts.iter() {
+        match &stmt.node {
+            StatementType::Return { value } => {
+                if let Some(v) = value {
+                    get_expression_unknowns(defined, unknowns, &v.node);
+                }
+            }
+            StatementType::Assign { targets, value } => {
+                get_expression_unknowns(defined, unknowns, &value.node);
+                for t in targets.iter() {
+                    get_pattern_match_unknowns(defined, unknowns, &t.node);
+                }
+            }
+            StatementType::AugAssign { target, value, .. } => {
+                get_expression_unknowns(defined, unknowns, &target.node);
+                get_expression_unknowns(defined, unknowns, &value.node);
+            }
+            StatementType::AnnAssign { target, value, .. } => {
+                if let Some(v) = value {
+                    get_expression_unknowns(defined, unknowns, &v.node);
+                }
+                get_pattern_match_unknowns(defined, unknowns, &target.node);
+            }
+            StatementType::Expression { expression } => {
+                get_expression_unknowns(defined, unknowns, &expression.node);
+            }
+            StatementType::If { test, body, orelse }
+            | StatementType::While { test, body, orelse } => {
+                get_expression_unknowns(defined, unknowns, &test.node);
+                get_statement_unknowns(defined, unknowns, body.as_slice());
+                if let Some(orelse) = orelse {
+                    get_statement_unknowns(defined, unknowns, orelse.as_slice());
+                }
+            }
+            StatementType::For { is_async, target, body, orelse, iter } => {
+                if *is_async {
+                    unimplemented!();
+                }
+                let mut scoped = defined.to_owned();
+                get_expression_unknowns(defined, unknowns, &iter.node);
+                get_expression_unknowns(defined, &mut scoped, &target.node);
+                get_statement_unknowns(&mut scoped, unknowns, body.as_slice());
+                if let Some(orelse) = orelse {
+                    get_statement_unknowns(&mut scoped, unknowns, orelse.as_slice());
+                }
+            }
+            StatementType::With { is_async, items, body } => {
+                if *is_async {
+                    unimplemented!();
+                }
+                let mut scoped = defined.to_owned();
+                for item in items.iter() {
+
+                }
+            }
+            _ => {}
+        }
+    }
+}
+
 pub fn resolve_signatures<'a>(ctx: &mut TopLevelContext<'a>, stmts: &'a [Statement]) {
     for stmt in stmts.iter() {
         match &stmt.node {