Blocked revisions 71824 via svnmerge

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  r71824 | mark.dickinson | 2009-04-24 13:46:53 +0100 (Fri, 24 Apr 2009) | 7 lines

  Issue #5816:
   - simplify parsing and printing of complex numbers
   - make complex(repr(z)) round-tripping work for complex
     numbers involving nans, infs, or negative zeros
   - don't accept some of the stranger complex strings
     that were previously allowed---e.g., complex('1..1j')
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