Sets all chemical potential values and returns a dictionary where
            the key is a sympy Symbol and the value is a float (chempot).

        Args:
            entry (SlabEntry): Computed structure entry of the slab
            delu_dict (Dict): Dictionary of the chemical potentials to be set as
                constant. Note the key should be a sympy Symbol object of the
                format: Symbol("delu_el") where el is the name of the element.
            delu_default (float): Default value for all unset chemical potentials

        Returns:
            Dictionary of set chemical potential values

def set_all_variables(self, delu_dict, delu_default):
        """
        Sets all chemical potential values and returns a dictionary where
            the key is a sympy Symbol and the value is a float (chempot).

        Args:
            entry (SlabEntry): Computed structure entry of the slab
            delu_dict (Dict): Dictionary of the chemical potentials to be set as
                constant. Note the key should be a sympy Symbol object of the
                format: Symbol("delu_el") where el is the name of the element.
            delu_default (float): Default value for all unset chemical potentials

        Returns:
            Dictionary of set chemical potential values
        """

        # Set up the variables
        all_delu_dict = {}
        for du in self.list_of_chempots:
            if delu_dict and du in delu_dict.keys():
                all_delu_dict[du] = delu_dict[du]
            elif du == 1:
                all_delu_dict[du] = du
            else:
                all_delu_dict[du] = delu_default

        return all_delu_dict