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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 _isValidTrigger(block, ch):
 """check if the trigger characters are in the right context, otherwise running the indenter might be annoying to the user """

        if ch == "" or ch == "\n":
            return True # Explicit align or new line

        match = rxUnindent.match(block.text())
        return match is not None and \
               match.group(3) == ""