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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 make_supercell(system, matrix, supercell=[1, 1, 1]):
 """ 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`. """

    user_supercell = [[1, supercell[0]], [1, supercell[1]], [1, supercell[1]]]
    system = create_supercell(system, matrix, supercell=user_supercell)
    return MolecularSystem.load_system(system)