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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 iterall(cls, target, branch, build, flags, platform=None):
 """Return an iterable for all available builds matching a particular build type"""

        flags = BuildFlags(*flags)
        for task in BuildTask.iterall(build, branch, flags, platform):
            yield cls(target, branch, task, flags, platform)