Replace a variable name, with a potentially new value.

        Parameters
        ----------
        old_key : str
            Current variable name to replace
        new_key : str
            New variable name to replace `old_key` with
        new_value : object
            Value to be replaced along with the possible renaming

def swapkey(self, old_key, new_key, new_value=None):
        """Replace a variable name, with a potentially new value.

        Parameters
        ----------
        old_key : str
            Current variable name to replace
        new_key : str
            New variable name to replace `old_key` with
        new_value : object
            Value to be replaced along with the possible renaming
        """
        if self.has_resolvers:
            maps = self.resolvers.maps + self.scope.maps
        else:
            maps = self.scope.maps

        maps.append(self.temps)

        for mapping in maps:
            if old_key in mapping:
                mapping[new_key] = new_value
                return