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Knocking on a wooden bathroom door from exterior perspective.
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Knocking on a wooden bathroom door, with one sharp knock from exterior perspective
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Knocking on a wooden bathroom door with two concise knocks from an exterior perspective.
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Knocking politely on a bathroom door four times, from an exterior perspective.
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Knocking on a wooden bathroom door impatiently six times from exterior perspective.
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Professional espresso machine - tapping portafilter three times.
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Knock on wooden door - medium, reflective space.
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