code: def missing(data: pd.Series) -> Any:
      """Count number of missing values.
  
      Args:
          data (pd.Series): Time series.
  
      Returns:
          int: Number of ``np.nan`` in ``data``.
      """
      return int(data.isna().sum())
  
file_path: tslumen/tslumen/profile/summary.py
imports: from typing import Any, Optional
  import numpy
  import pandas
  from statsmodels.tsa.tsatools import freq_to_period
  from tslumen.profile.base import ProfilingFunction, TypeSeriesFrame
label_desc: Use image node_id 10 for calling a global function with example usage: missing(data) and returns: int