Add stubs for symtable (#1048)

* add symtable
* fix name

stdlib/2and3/symtable.pyi

@@ -0,0 +1,45 @@
+# Stubs for symtable (Python 2 and 3)
+
+import sys
+from typing import List, Sequence, Tuple
+
+class SymbolTable(object):
+    def get_type(self) -> str: ...
+    def get_id(self) -> int: ...
+    def get_name(self) -> str: ...
+    def get_lineno(self) -> int: ...
+    def is_optimized(self) -> bool: ...
+    def is_nested(self) -> bool: ...
+    def has_children(self) -> bool: ...
+    def has_exec(self) -> bool: ...
+    if sys.version_info < (3, 0):
+        def has_import_star(self) -> bool: ...
+    def get_identifiers(self) -> Sequence[str]: ...
+    def lookup(self, name: str) -> Symbol: ...
+    def get_symbols(self) -> List[Symbol]: ...
+    def get_children(self) -> List[SymbolTable]: ...
+
+class Function(SymbolTable):
+    def get_parameters(self) -> Tuple[str, ...]: ...
+    def get_locals(self) -> Tuple[str, ...]: ...
+    def get_globals(self) -> Tuple[str, ...]: ...
+    def get_frees(self) -> Tuple[str, ...]: ...
+
+class Class(SymbolTable):
+    def get_methods(self) -> Tuple[str, ...]: ...
+
+class Symbol(object):
+    def get_name(self) -> str: ...
+    def is_referenced(self) -> bool: ...
+    def is_parameter(self) -> bool: ...
+    def is_global(self) -> bool: ...
+    def is_declared_global(self) -> bool: ...
+    def is_local(self) -> bool: ...
+    if sys.version_info >= (3, 6):
+        def is_annotated(self) -> bool: ...
+    def is_free(self) -> bool: ...
+    def is_imported(self) -> bool: ...
+    def is_assigned(self) -> bool: ...
+    def is_namespace(self) -> bool: ...
+    def get_namespaces(self) -> Sequence[SymbolTable]: ...
+    def get_namespace(self) -> SymbolTable: ...