Two dataframes merged

[Ecniv]

for i,r in checkout.iterrows():
    ind = -1
    f = cleaned[cleaned['atime'].isnull()]
    print('1',len(f))
    #print(f.head(4))
    if f is not None:
        f = f[f['date']==r['date']]
    print('2',len(f))
    #print(f.head(4))
    if f is not None:
        f = f[f['dtime']<r['atime']]
    print('3',len(f))
    #print(f.head(4))
    if f is not None:
        ind = iloc(f)
    print('4',f.head(4))
    if ind>=0:
        print(ind)
        cleaned[ind]['atime','arrival','cost']=r['atime','arrival','cost']
    break

Still testing - this almost worked but errors as it cannot find the index of the cleaned to update the values...