def checksum_valid?(local_file: nil, rw_pw: nil, ro_pw: nil, unmount: true)
      return false unless @checksum
      new_checksum = calculate_checksum(
        type: @checksum_type,
        local_file: local_file,
        rw_pw: rw_pw,
        ro_pw: ro_pw,
        unmount: unmount
      )
      new_checksum == @checksum
    end
def checksum_valid?(local_file: nil, rw_pw: nil, ro_pw: nil, unmount: true)
      return false unless @checksum
      new_checksum = calculate_checksum(
        type: @checksum_type,
        local_file: local_file,
        rw_pw: rw_pw,
        ro_pw: ro_pw,
        unmount: unmount
      )
      new_checksum == @checksum
    end
Is the checksum for this pkg is valid?

 @param local_file [String, Pathname] A local copy of the pkg file. BE SURE
   it's identical to the one on the server. If omitted, the master dist.
   point will be mounted and the file read from there.

 @param rw_pw [String] The read-write password for mounting the master dist
   point. Either this or the ro_pw must be provided if no local_file

 @param ro_pw [String] The read-onlypassword for mounting the master dist
   point. Either this or the rw_pw must be provided if no local_file

 @param unmount [Boolean] Unmount the master dist point after using it.
   Only used if the dist point is mounted. default: true

 @return [Boolean] false if there is no checksum for this pkg, otherwise,
   does the calculated checksum match the one stored for the pkg?