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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 search_greater(values, target):
 """ Return the first index for which target is greater or equal to the first item of the tuple found in values """

    first = 0
    last = len(values)

    while first < last:
        middle = (first + last) // 2
        if values[middle][0] < target:
            first = middle + 1
        else:
            last = middle

    return first