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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 bump_version(v: version.Version, level: str) -> str: """Version bump logic"""

    release: List[int] = list(v.release)
    stage: Optional[str]
    pre: Optional[int]
    stage, pre = v.pre if v.pre else (None, None)
    dev: Optional[int] = v.dev
    post: Optional[int] = v.post

    if level in ("major", "minor", "patch"):
        segments = 0
        if level == "major":
            # if the version code is in format of x.0.0, and pre/dev is not empty
            # do not increase the version number
            segments = 1
        elif level == "minor":
            # if the version code is in format of x.x.0, and pre/dev is not empty
            # do not increase the version number
            segments = 2
        elif level == "patch":
            # if the version code is in format of x.x.x, and pre/dev is not empty
            # do not increase the version number
            segments = 3
        if not any(release[segments:]) and (stage is not None or dev is not None):
            pass
        else:
            release[segments - 1] += 1
        release[segments:] = [0] * max(len(release) - segments, 0)
        stage = pre = post = dev = None
    elif level == "alpha":
        if stage is None:
            if dev is None:
                release[-1] += 1
            stage, pre = "a", 1
        elif stage > "a":
            release[-1] += 1
            stage, pre = "a", 1
        elif stage == "a":
            pre += 1
        post = dev = None
    elif level == "beta":
        if stage is None:
            if dev is None:
                release[-1] += 1
            stage, pre = "b", 1
        elif stage > "b":
            release[-1] += 1
            stage, pre = "b", 1
        elif stage == "b":
            pre += 1
        elif stage < "b":
            pre = 1
            stage = "b"
        post = dev = None
    elif level == "post":
        if post is not None:
            post += 1
        else:
            post = 1
        dev = None
    elif level == "dev":
        if dev is not None:
            dev += 1
        else:
            if stage:
                pre += 1
            else:
                release[-1] += 1
            dev = 1

    ver = ".".join(str(i) for i in release)
    if stage is not None:
        ver += f"{stage}{pre}"
    if post is not None:
        ver += f".post{post}"
    if dev is not None:
        ver += f".dev{dev}"

    return ver