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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _complete_word(self, symbol, attribute):
 """Suggests context completions based exclusively on the word preceding the cursor."""

        #The cursor is after a %(,\s and the user is looking for a list
        #of possibilities that is a bit smarter that regular AC.
        if self.context.el_call in ["sub", "fun", "assign", "arith"]:
            if symbol == "":
                #The only possibilities are local vars, global vars or functions
                #presented in that order of likelihood. 
                return self._complete_values()
            else:
                #It is also possible that subroutines are being called, but that
                #the full name hasn't been entered yet.
                return self._complete_values(symbol)
        else:
            return self.context.module.completions(symbol, attribute, True)