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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 base26(x, _alphabet=string.ascii_uppercase):
 """Return positive ``int`` ``x`` as string in bijective base26 notation. ['', 'A', 'B', 'Z', 'AA', 'AB', 'ZZ', 'AAA', 'AAB'] 'SPAM' 'IV' """

    result = []
    while x:
        x, digit = divmod(x, 26)
        if not digit:
            x -= 1
            digit = 26
        result.append(_alphabet[digit - 1])
    return ''.join(result[::-1])