input: Write a Python function to connect to an SQLite database, execute a query, manipulate the data using pandas, and update the database.
  assert df['new_col'].equals(pd.Series([3, 7, 11]))
  assert df.shape == (3, 4)
  assert 'new_col' in df.columns
output: import sqlite3
  import pandas as pd
  
  def manipulate_sqlite_db(db_path, query):
      # Connect to the SQLite database
      conn = sqlite3.connect(db_path)
      
      # Execute the query and load data into a pandas DataFrame
      df = pd.read_sql_query(query, conn)
      
      # Add a new column 'new_col' to the DataFrame
      df['new_col'] = df.sum(axis=1)
      
      # Update the database with the modified DataFrame
      df.to_sql('updated_table', conn, if_exists='replace', index=False)
      
      # Close the connection
      conn.close()
      
      return df