How do you replace values in one column with values in another when condition is not met with Python

Question

I have some inconsistent data with 5 columns. The two I'm focussing on are - 'Account Name' and 'User ID'. All the Account names should contain a 7 character string. If it doesn't I want to replace if with the ID in 'User ID'. Example data:

Account Name	User ID
JB05737	JB05737
bg@***.com	BG49568
GV95577	GV95577

I want to get:

Account Name	User ID
JB05737	JB05737
BG49568	BG49568
GV95577	GV95577

I have tried the following codes and got errors:

Reports.loc[Reports['Account Name'].astype(str).map(len) != 7] = Reports[Reports['User ID']].astype(str)

Reports.loc[Reports['Account Name'].astype(str).map(len) != 7].replace(Reports['User ID'])

    if (Reports.loc['Account Name'].map(len) != 7):
        Reports.loc[i, 'Account Name']==Reports.loc[i, 'User ID']```

```Reports.loc[Reports['Account Name'].map(len) != 7, 'Account Name] = Reports.loc[Reports['Account Name'].map(len) != 7,'User ID']```


The errors have included: shape errors, invalid syntax, ...not in index

Any suggestions?

Answer 1

somthing like this..

for col1, id in df.itertuples(index=False):
  print("Iterating both columns:\n",a, b)
  if len(id) > 7:
    df['col1'].replace('col1', 'id')

Answer 2

This code worked for me

Reports['Account Name']=Reports['User ID'].where(Reports['Account Name'].map(len)>7,Reports['User ID'])