Blocked revisions 68843,68845 via svnmerge

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  r68843 | raymond.hettinger | 2009-01-21 14:31:50 -0600 (Wed, 21 Jan 2009) | 1 line

  Simplify explanation of multiset operations by removing restrictions on negative inputs.
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  r68845 | raymond.hettinger | 2009-01-21 17:12:51 -0600 (Wed, 21 Jan 2009) | 1 line

  Tighten-up the docs for Counter().
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