parameters: (self, extent)
docstring: Fetch block contents from disk given extents
docstring_summary: Fetch block contents from disk given extents
docstring_tokens: Fetch block contents from disk given extents
function: def fetchBlock(self, extent):
  		'''Fetch block contents from disk given extents'''
  		with open(self.inFileName(extent.fn), "rb") as f:
  			f.seek(extent.offset)
  			return f.read(extent.size)
function_tokens: def fetchBlock ( self , extent ) : with open ( self . inFileName ( extent . fn ) , "rb" ) as f : f . seek ( extent . offset ) return f . read ( extent . size )