add context manager test with threading.Lock which previously failed in Py2.6 (by Wouter Bolsterlee)

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rename : tests/run/withstat_py.py => tests/run/withstat_py27.py

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extra : amend_source : c827dfd2e781c1a7e1b982601b6ee8e826d5b4ed

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extra : amend_source : 1bdb5f011d5234a8631b04ac0e5f9df9fe6a4de0
extra : transplant_source : %A1Z%B1%2C%CE%B4%D6%20SMS%CA%12%7D%2B%1A%FC%00%E1%CD

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extra : transplant_source : G%E0%FEP%AA%EC%9B%8B%06G4%C1x%17%F5Q4F%3Ep

make CyFunction's inheritance from PyCFunction visible at the Python level to let inspect.isbuiltin(cyfunction) return True

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extra : transplant_source : %8D%99%BA%9D%13e%1E%9E%A8%88%9D%88m%F4D%DFw_%2B%F2

code objects: add number of kwonly args to number of regular arguments in Py2 (which does not support kwonly arguments for Python functions) to make sure they are still visible for introspection

nogil and more exported functions in numpy.math pxd

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extra : amend_source : 2797e0ad678cc0a33a2548a8a20b00475bc8a21b

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extra : amend_source : 8474ebfc7b6ab33b8cca9e4a478c54b2bee5f2fc

fix in-place assignments of arbitrary objects to variables with inferred Python builtin/extension types