1 | initial version |

There is a minor issue in your code:

```
F = GF(2)
R.<x> = k[]
```

Presumably `F`

should be `k`

or vice versa. The major issue with using this in Python is that `R.<x> = k[]`

is not allowable Python syntax. Sage preparses it first. You can find out how it does this as follows:

```
sage: k = GF(2)
sage: preparse('R.<x> = k[]')
"R = k['x']; (x,) = R._first_ngens(1)"
```

So you should be able to do

```
from sage.all import *
k = GF(2)
R = k['x']; (x,) = R._first_ngens(1)
K = F.extension(x^4 + x + 1, 'a')
```

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