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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 assert_keys_exist(self, caller, *keys):
 """Assert that context contains keys. Args: keys: validates that these keys exists in context caller: string. calling function or module name - this used to construct error messages Raises: KeyNotInContextError: When key doesn't exist in context. """

        assert keys, ("*keys parameter must be specified.")
        for key in keys:
            self.assert_key_exists(key, caller)