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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 write_FORCE_CONSTANTS(force_constants, filename='FORCE_CONSTANTS', p2s_map=None):
 """Write force constants in text file format. Parameters force_constants: ndarray Force constants shape=(n_satom,n_satom,3,3) or (n_patom,n_satom,3,3) dtype=double filename: str Filename to be saved p2s_map: ndarray Primitive atom indices in supercell index system dtype=intc """


    lines = get_FORCE_CONSTANTS_lines(force_constants, p2s_map=p2s_map)
    with open(filename, 'w') as w:
        w.write("\n".join(lines))