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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 postbuild_arch(self, arch):
        '''Run any post-build tasks for the Recipe. By default, this checks if
        any postbuild_archname methods exist for the archname of the
        current architecture, and runs them if so.
        '''
        postbuild = "postbuild_{}".format(arch.arch)
        if hasattr(self, postbuild):
            getattr(self, postbuild)()