<SYSTEM_TASK:>
Given the following text description, write Python code to implement the functionality described below step by step
<END_TASK>
<USER_TASK:>
Description:
 Loading data
Step1:  loading file with very lighty dark
It's the last MUV file that has the very bright dark image.
Step2:  The DarkIntegration data shows that there are 2 observations of darks, approx 22 minutes apart
Step3:  Let's look at the original darks. There are 2 available
Step4:  As one can see, they are strongly different. The last dark looks similar to a usual light image.
<ASSISTANT_TASK:>
Python Code:
from iuvs import io
%autocall 1
import os
files = !ls ~/data/iuvs/level1b/*.gz
for file in files:
    print(os.path.basename(file))
Explanation: Loading data
End of explanation
l1b = io.L1BReader(files[-1])
Explanation: loading file with very lighty dark
It's the last MUV file that has the very bright dark image.
End of explanation
l1b.DarkIntegration
Explanation: The DarkIntegration data shows that there are 2 observations of darks, approx 22 minutes apart:
End of explanation
l1b.detector_dark.shape
def compare_darks(dark1, dark2):
    fig, ax = subplots(nrows=2, figsize=(10,8))
    ax[0].imshow(dark1)
    ax[1].imshow(dark2)
compare_darks(*l1b.detector_dark) # this trick puts the first axis of a cube into a function
Explanation: Let's look at the original darks. There are 2 available:
End of explanation
l1b.DarkEngineering
Explanation: As one can see, they are strongly different. The last dark looks similar to a usual light image.
End of explanation
<END_TASK>