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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 clean_builds(self, _args):
 """Delete all build caches for each recipe, python-install, java code and compiled libs collection. This does *not* delete the package download cache or the final distributions. You can also use clean_recipe_build to delete the build of a specific recipe. """

        ctx = self.ctx
        if exists(ctx.build_dir):
            shutil.rmtree(ctx.build_dir)
        if exists(ctx.python_installs_dir):
            shutil.rmtree(ctx.python_installs_dir)
        libs_dir = join(self.ctx.build_dir, 'libs_collections')
        if exists(libs_dir):
            shutil.rmtree(libs_dir)