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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 _join(segments):
 """simply list by joining adjacent segments."""

    new = []
    start = segments[0][0]
    end = segments[0][1]
    for i in range(len(segments)-1):
        if segments[i+1][0] != segments[i][1]:
            new.append((start, end))
            start = segments[i+1][0]
        end = segments[i+1][1]
    new.append((start, end))
    return new