is there a way where I could save the entire difference between two diff in a text file?

Suppose I wanted all the changes between `A1` and `A10` on `master` branch.

```
--A11-A10-A9-A8-A7-A6-A5-A4-A3-A2-A1-master

```

Or, is there a way where I could get the entire diff in Terminal which I could copy+paste?