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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 combine_dictionaries(a, b):
 """ returns the combined dictionary. a's values preferentially chosen """


    c = {}
    for key in list(b.keys()): c[key]=b[key]
    for key in list(a.keys()): c[key]=a[key]
    return c