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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 get_energy_relax_structure_buckingham(structure, gulp_cmd='gulp', keywords=('optimise', 'conp'), valence_dict=None):
 """ Relax a structure and compute the energy using Buckingham potential. Args: structure: pymatgen.core.structure.Structure gulp_cmd: GULP command if not in standard place keywords: GULP first line keywords valence_dict: {El: valence}. Needed if the structure is not charge neutral. """

    gio = GulpIO()
    gc = GulpCaller(gulp_cmd)
    gin = gio.buckingham_input(
        structure, keywords, valence_dict=valence_dict
    )
    gout = gc.run(gin)
    energy = gio.get_energy(gout)
    relax_structure = gio.get_relaxed_structure(gout)
    return energy, relax_structure