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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def merge(data,skip=50,fraction=1.0):
 """Merge one every 'skip' clouds into a single emcee population, using the later 'fraction' of the run."""


    w,s,d = data.chains.shape
    
    start = int((1.0 - fraction) * s)
    total = int((s - start) / skip)
        
    return data.chains[:,start::skip,:].reshape((w*total,d))