Histogram multiple columns, percentage per columns same plot

Question

I have this dataframe(df_histo):

ID   SA   WE   EE
1   NaN  320  23.4 
2   234  2.3  NaN
..  ..  ..   ..
345 1.2  NaN  234

I can plot a correct histogram if I use density=True,

buckets = [0,250,500,1000,1500,2000,2500,3000,3500,4000,4500,5000]

plt.hist(df_histo, bins=buckets, label=dfltabv_histo.columns, density=True)

however I want to visualize the data(1 histogram) in total percentages for each country. That is, what percentage each bins represents in that country

the closest attempt has been this(with individual columns it works):

plt.hist(dfltabv_histo, bins=buckets, label=dfltabv_histo.columns, weights=np.ones(len(dfltabv_histo)) / len(dfltabv_histo))

plt.gca().yaxis.set_major_formatter(PercentFormatter(1))

ValueError: weights should have the same shape as x