Fix 'freeze' demo

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extra : transplant_source : %D6h%3C%E4%02%B9%D5%D1%B0%95%5Bly.%18%B3%D20%A7%EC

Use more recent version of Python for documented examples

Implement PEP 465: dedicated infix operator for matrix multiplication

treat unknown (builtin) names as potential globals instead of requiring them to be builtins at runtime

DOC: Updates EPD references to refer to Canopy

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extra : transplant_source : %CA%BB%21%89%8CQ%A0F%3EN%E5%7Cs%01%5D%060A%C8%AF

make encoding setup code safer by not expecting sys.getdefaultencoding() to safely return a bytes object

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extra : transplant_source : cZx%3E%03l%AC%EDK%E3%C2%F2%2C%9BV%E5%EC%5D%B7%C8

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extra : transplant_source : M%D5%2C%C2%15%9E%3C%BC%3C%89%25n%95%DF%5C%B8%B5%C5%B8%D9