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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 decompose_code(code):
 """ Decomposes a MARC "code" into tag, ind1, ind2, subcode """

    code = "%-6s" % code
    ind1 = code[3:4]
    if ind1 == " ": ind1 = "_"
    ind2 = code[4:5]
    if ind2 == " ": ind2 = "_"
    subcode = code[5:6]
    if subcode == " ": subcode = None
    return (code[0:3], ind1, ind2, subcode)