code: def call(self, **kwargs):
          
          if not hasattr(self, 'funcs'):
              raise StartupError('startup cannot be called again')
          for name, var in self.variables.items():
              var.name = name
          self.variable_values.update(kwargs)
          for name in self.variable_values:
              self.variables[name].name = name
          queue = Closure.sort(self.satisfied)
          queue.extend(_write_values(self.variable_values, self.variables))
          while queue:
              closure = queue.pop(0)
              writeto = closure.call()
              self.funcs.remove(closure.func)
              queue.extend(_notify_reader_writes(writeto))
          if self.funcs:
              raise StartupError('cannot satisfy dependency for %r' % self.funcs)
          values = {
              name: var.read_latest() for name, var in self.variables.items()
          }
          # Call _release() on normal exit only; otherwise keep the dead body for
          # forensic analysis.
          self._release()
          return values
docs: Call all the functions that have previously been added to the
          dependency graph in topological and lexicographical order, and
          then return variables in a ``dict``.
  
          You may provide variable values with keyword arguments.  These
          values will be written and can satisfy dependencies.
  
          NOTE: This object will be **destroyed** after ``call()`` returns
          and should not be used any further.