def make_supercell(system, matrix, supercell=[<NUM_LIT:1>, <NUM_LIT:1>, <NUM_LIT:1>]):
user_supercell = [[<NUM_LIT:1>, supercell[<NUM_LIT:0>]], [<NUM_LIT:1>, supercell[<NUM_LIT:1>]], [<NUM_LIT:1>, supercell[<NUM_LIT:1>]]]<EOL>system = create_supercell(system, matrix, supercell=user_supercell)<EOL>return MolecularSystem.load_system(system)<EOL>
Return a supercell.

This functions takes the input unitcell and creates a supercell of it that
is returned as a new :class:`pywindow.molecular.MolecularSystem`.

Parameters
----------
system : :attr:`pywindow.molecular.MolecularSystem.system`
    The unit cell for creation of the supercell

matrix : :class:`numpy.array`
    The unit cell parameters in form of a lattice.

supercell : :class:`list`, optional
    A list that specifies the size of the supercell in the a, b and c
    direction. (default=[1, 1, 1])

Returns
-------
:class:`pywindow.molecular.MolecularSystem`
    Returns the created supercell as a new :class:`MolecularSystem`.