parameters: (self, instr)
docstring: Position immediately before the given instruction.  The current block
          is also changed to the instruction's basic block.
docstring_summary: Position immediately before the given instruction.  The current block
          is also changed to the instruction's basic block.
docstring_tokens: Position immediately before the given instruction . The current block is also changed to the instruction s basic block .
function: def position_before(self, instr):
          """
          Position immediately before the given instruction.  The current block
          is also changed to the instruction's basic block.
          """
          self._block = instr.parent
          self._anchor = self._block.instructions.index(instr)
function_tokens: def position_before ( self , instr ) : self . _block = instr . parent self . _anchor = self . _block . instructions . index ( instr )