Add new APIs to core.contract:

- functions_inherited
- functions_not_inherited
- modifiers_inherited
- modifiers_not_inherited
- functions_and_modifiers_inherited
- functions_and_modifiers_not_inherited
- functions_entry_points
- get_functions_overridden_by

slither/core/declarations/contract.py

@@ -85,12 +85,6 @@ class Contract(ChildSlither, SourceMapping):
     def enums_as_dict(self):
         return self._enums
 
-    @property
-    def modifiers(self):
-        '''
-            list(Modifier): List of the modifiers
-        '''
-        return list(self._modifiers.values())
 
     def modifiers_as_dict(self):
         return self._modifiers
@@ -113,6 +107,74 @@ class Contract(ChildSlither, SourceMapping):
         '''
         return [f for f in self.functions if f.contract != self]
 
+    @property
+    def functions_not_inherited(self):
+        '''
+            list(Function): List of the functions defined within the contract (not inherited)
+        '''
+        return [f for f in self.functions if f.contract == self]
+
+    @property
+    def functions_entry_points(self):
+        '''
+            list(Functions): List of public and external functions
+        '''
+        return [f for f in self.functions if f.visibility in ['public', 'external']]
+
+    @property
+    def modifiers(self):
+        '''
+            list(Modifier): List of the modifiers
+        '''
+        return list(self._modifiers.values())
+
+    @property
+    def modifiers_inherited(self):
+        '''
+            list(Modifier): List of the inherited modifiers
+        '''
+        return [m for m in self.modifiers if m.contract != self]
+
+    @property
+    def modifiers_not_inherited(self):
+        '''
+            list(Modifier): List of the modifiers defined within the contract (not inherited)
+        '''
+        return [m for m in self.modifiers if m.contract == self]
+
+    @property
+    def functions_and_modifiers(self):
+        '''
+            list(Function|Modifier): List of the functions and modifiers
+        '''
+        return self.functions + self.modifiers
+
+    @property
+    def functions_and_modifiers_inherited(self):
+        '''
+            list(Function|Modifier): List of the inherited functions and modifiers
+        '''
+        return self.functions_inherited + self.modifiers_inherited
+
+    @property
+    def functions_and_modifiers_not_inherited(self):
+        '''
+            list(Function|Modifier): List of the functions and modifiers defined within the contract (not inherited)
+        '''
+        return self.functions_not_inherited + self.modifiers_not_inherited
+
+    def get_functions_overridden_by(self, function):
+        '''
+            Return the list of functions overriden by the function
+        Args:
+            (core.Function)
+        Returns:
+            list(core.Function)
+
+        '''
+        candidates = self.functions_inherited
+        return [f for f in candidates if f.name == function]
+
     @property
     def all_functions_called(self):
         '''