code: def _data_integrity_check(data):
      
      deps = []
      for command in data['commands']:
          if 'dependencies' in data['commands'][command]:
              for d in data['commands'][command]['dependencies']:
                  deps.append({
                      'd': d,
                      'c': command
                  })
      for d in deps:
          if d['d'] not in data['commands']:
              raise error.ProjectfileError({
                  'error': error.PROJECTFILE_INVALID_DEPENDENCY.format(d['d'], d['c'])
              })
docs: Checks if all command dependencies refers to and existing command. If not, a ProjectfileError
      will be raised with the problematic dependency and it's command.
  
      :param data: parsed raw data set.
      :return: None