def _get_depencency_var_name(self, dependency):
for dep_path, var_name in self.dependencies:<EOL><INDENT>if dep_path == dependency:<EOL><INDENT>return var_name<EOL><DEDENT><DEDENT>
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