started work on assignment operators

lexer_token.py

@@ -23,6 +23,10 @@ class TokenType(Enum):
 
 	# Assignment symbols
 	EQ = "EQ"
+	PLUS_EQ = "PLUS_EQ"
+	MINUS_EQ = "MINUS_EQ"
+	MUL_EQ = "MUL_EQ"
+	DIV_EQ = "DIV_EQ"
 
 	# Comparison symbols
 	LT = "<"
@@ -43,6 +47,7 @@ class TokenType(Enum):
 	SEMICOLON = "SEMICOLON"
 	COMMA = "COMMA"
 	DOLLARSIGN = "DOLLARSIGN"
+	BANG = "BANG"
 
 	# Keywords
 	RETURN = "RETURN"