def METHOD_NAME(pig, label=None):
    """Plot a black hole mass function from a FOF table."""
    bf = BigFile(pig)
    redshift = 1/bf['Header'].attrs['Time']-1
    hh = bf['Header'].attrs['HubbleParam']
    lbox = bf['Header'].attrs['BoxSize']/1000/hh
    lfm = getbmf(bf,lbox, hh)
    plt.plot(lfm[0],lfm[1],label=(label or '')+' z=%.1f'%redshift)
    plt.fill_between(lfm[0],lfm[2],lfm[3],alpha=0.2)
    plt.xlabel(r'$\mathrm{log}_{10} [M_{\rm BH}/M_{\odot}]$',fontsize=17)
    plt.ylabel(r'$\mathrm{log}_{10} \phi/[\mathrm{dex}^{-1} \mathrm{Mpc}^{-3}]$',fontsize=15)
    plt.xlim(6,12)
    plt.ylim(-7,-2.5)
    plt.title('BH Mass function',fontsize=15)
    plt.legend(fontsize=15)