I have a two list one list contain default dtypes of the column in dataframe and second list contain changing dtypes list how to use which apporach to handel this problem .suppose
Columns Name is ['NameID','Age','Address','DOB']

```
default_dty=['int64',int64,'object','object']

```

When we check my default dtype is

```
NameId  int64
Age     int64
Address object
DOB     object

required_dty=['object',object','object','date']

```

What output I required

```
NameId  object
Age     object
Address object
DOB     date

```

I want changes using loop because I have 30 columns in my dataframe,so I don't do the manually
my code is :

```
for col,rdt in zip(cname.columns,req_dty):
    # data[colu]=data[colu].astype(rdt)
    if 'date' in rdt:    
        a=redt.index('date')
        data[c[a]]=pd.to_datetime(data[c[a]],unit='ns')
    else:
        data[colu]=data[colu].astype(rdt)

```

But It's not working.
Pls Help.....!