I have a list in Python and I am looking to invert every pair of elements in the list. Here is the list:

```
list_ty = ['many_ord','many','12_FH_Temp_ord','12_FH_Temp','Celsius_ord','Celsius','Pressure_Pas_ord','Pressure_Pas','Kelvin_ord','Kelvin']

```

Here is what I would like to get:

```
list_out = ['many','many_ord','12_FH_Temp','12_FH_Temp_ord','Celsius','Celsius_ord','Pressure_Pas','Pressure_Pas_ord','Kelvin','Kelvin_ord']

```

**Additional Information:**

There will always be an even number of elements in the list.

The item ending with `_ord` will always come before the item without `_ord`.

**Question:**

Is there a way to reverse the order of each item ending with `_ord` and the following (associated) item without `_ord`?