I have the table from ImDB with actors. 

[![enter image description here](https://i.stack.imgur.com/eSvUS.png)](https://i.stack.imgur.com/eSvUS.png)

From this table I want to drop all rows where **imdb\_actors.birthYear** is missing or is less than 1950 and also drope those where **imdb\_actors.deathYear** has some value. 

*Idea is to get a dataset with actors who are alive and not retired.*

```
imdb_actors.birthYear.dtype
Out:dtype('O')

```

And I can't convert to string, this doesn't help: `imdb_actors['birthYear'] = imdb_actors['birthYear'].astype('|S')`. It just ruins all years.

That's why I can't execute: `imdb_actors[imdb_actors.birthYear >= 1955]`
When I try `imdb_actors.birthYear.astype(str).astype(int)` I get the message: `ValueError: invalid literal for int() with base 10: '\\N'`

What will be the way to drop missing and apply >= 1950 condition?