human
Solve the following python programming problem given the following code:
def _gen_code(self) : 
    'Generate code for the list of expressions provided using the common sub-expression eliminator to separate out portions that are computed multiple times.' 
    self.code = { 
        
} 
    def match_key(expr) : 
        if (type (expr) is dict) : 
            code = { 
                
} 
            for key in expr.keys () : 
                code [key] = match_key (expr [key]) 
else : 
            arg_list = [e for e in expr.atoms () if e.is_Symbol] 
            code = self._expr2code (arg_list, expr) 
return code 
self.code = match_key (match_key.expressions) 

    
    

    Fix the buggy line: self.code = match_key (match_key.expressions)
assistant
#Here is Python program to fix the buggy line: self.

self.code = match_key (self.expressions)