"how long is a piece of string" meaning in English

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      "glosses": [
        "Used as a response to a question such as \"How long will it take?\" or \"How big is it?\" when the length or size is unknown, infinite, variable, or relative."
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        [
          "infinite",
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          "variable",
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          "relative",
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      "raw_glosses": [
        "(colloquial, often humorous, rhetorical question) Used as a response to a question such as \"How long will it take?\" or \"How big is it?\" when the length or size is unknown, infinite, variable, or relative."
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        "Used as a response to a question such as \"How long will it take?\" or \"How big is it?\" when the length or size is unknown, infinite, variable, or relative."
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        "(colloquial, often humorous, rhetorical question) Used as a response to a question such as \"How long will it take?\" or \"How big is it?\" when the length or size is unknown, infinite, variable, or relative."
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