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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 parametrize(params):
 """Return list of params as params. 'a' 'a[b]' 'a[b][c]' """

    returned = str(params[0])
    returned += "".join("[" + str(p) + "]" for p in params[1:])
    return returned