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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 unalias_tool(self, context_name, tool_name):
 """Deregister an alias for a specific tool. Args: context_name (str):
 Context containing the tool. tool_name (str):
 Name of tool to unalias. """

        data = self._context(context_name)
        aliases = data["tool_aliases"]
        if tool_name in aliases:
            del aliases[tool_name]
            self._flush_tools()