Thanks chris nearly tempted lol but then I read this
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The yellow-staining mushroom (Agaricus xanthodermus), for instance, which can leave you racing between basin and toilet for days on end, is easily mistaken for both the field mushroom (Agaricus campestris) and the cultivated mushroom (Agaricus bisporus), the usual white number that you buy in supermarkets. The only way to tell some lookalikes apart is to stick them on a piece of paper and check the colour of the spores that drop from their undercarriages. That's every bit as tedious as it sounds.
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