code: def _parse_scalars(scalars):
          
          scalar_dict = {}
  
          # Scalars are defined in a fixed two-level hierarchy within the definition file.
          # The first level contains the category name, while the second level contains the
          # probe name (e.g. "category.name: probe: ...").
          for category_name in scalars:
              category = scalars[category_name]
  
              for probe_name in category:
                  # We found a scalar type. Go ahead and parse it.
                  scalar_definition = category[probe_name]
                  # We pass |strict_type_checks=False| as we don't want to do any check
                  # server side. This includes skipping the checks for the required keys.
                  scalar_info = ScalarType(category_name, probe_name, scalar_definition,
                                           strict_type_checks=False)
                  scalar_dict[scalar_info.label] = scalar_info
  
          return scalar_dict
docs: Parse the scalars from the YAML file content to a dictionary of ScalarType(s).
          :return: A dictionary { 'full.scalar.label': ScalarType }