def get_lipid_vdwradii(outdir=os.path.curdir, libdir=None):
vdwradii_dat = os.path.join(outdir, "<STR_LIT>")<EOL>if libdir is not None:<EOL><INDENT>filename = os.path.join(libdir, '<STR_LIT>')  <EOL>if not os.path.exists(filename):<EOL><INDENT>msg = '<STR_LIT>'.format(**vars())<EOL>logger.exception(msg)<EOL>raise OSError(msg, errno.ENOENT)<EOL><DEDENT><DEDENT>else:<EOL><INDENT>try:<EOL><INDENT>filename = os.path.join(os.environ['<STR_LIT>'], '<STR_LIT>')<EOL><DEDENT>except KeyError:<EOL><INDENT>try:<EOL><INDENT>filename = os.path.join(os.environ['<STR_LIT>'], '<STR_LIT>', '<STR_LIT>')<EOL><DEDENT>except KeyError:<EOL><INDENT>msg = "<STR_LIT>"<EOL>logger.exception(msg)<EOL>raise OSError(msg, errno.ENOENT)<EOL><DEDENT><DEDENT><DEDENT>if not os.path.exists(filename):<EOL><INDENT>msg = "<STR_LIT>".format(**vars())<EOL>logger.exception(msg, errno.ENOENT)<EOL>raise OSError(msg)<EOL><DEDENT>patterns = vdw_lipid_resnames + list({x[:<NUM_LIT:3>] for x in vdw_lipid_resnames})<EOL>with open(vdwradii_dat, '<STR_LIT:w>') as outfile:<EOL><INDENT>outfile.write('<STR_LIT>')<EOL>for resname in patterns:<EOL><INDENT>for atom,radius in vdw_lipid_atom_radii.items():<EOL><INDENT>outfile.write('<STR_LIT>'.format(**vars()))<EOL><DEDENT><DEDENT>with open(filename, '<STR_LIT:r>') as infile:<EOL><INDENT>for line in infile:<EOL><INDENT>outfile.write(line)<EOL><DEDENT><DEDENT><DEDENT>logger.debug('<STR_LIT>'.format(**vars()))<EOL>return realpath(vdwradii_dat)<EOL>
Find vdwradii.dat and add special entries for lipids.

    See :data:`gromacs.setup.vdw_lipid_resnames` for lipid
    resnames. Add more if necessary.