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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 _get_depencency_var_name(self, dependency):
 """ Returns the variable name assigned to the given dependency or None if the dependency has not yet been registered. Args: dependency (str):
 Thet dependency that needs to be imported. Returns: str or None """

        for dep_path, var_name in self.dependencies:
            if dep_path == dependency:
                return var_name