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

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extra : transplant_source : %F3%9A%B7r%F7%DB%C7%88%2B%D2%A4%9C%5E%0FT%B8_XS%D2

fix ASCII compatibility check in __Pyx_init_sys_getdefaultencoding_params(): strncmp() stops at first NUL byte which is the first byte in this case (i.e. no comparison is done at all)

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extra : transplant_source : A%2B%5BO%82%05%F7%DEm/%8Ao%08%121%96%8Ao%AB%8C

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extra : rebase_source : 4cc5a2b5b9044e06fca82d216aa5a3c919abf033