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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 build(ctx, output="html"):
 """ Build docs. """


    with ctx.cd(ctx.docs.directory.as_posix()):
        build_command = f"make {output}"
        report.info(ctx, "docs.build", f"building {output!r} documentation")
        ctx.run(build_command)