input: Write a python function to query the database for all entries where age is greater than a specified value.
  assert query_ages_greater_than(25) == [('Alice', 30), ('Bob', 40)]
  assert query_ages_greater_than(18) == [('John', 20), ('Alice', 30), ('Bob', 40)]
  assert query_ages_greater_than(50) == []
output: def query_ages_greater_than(age):
      import sqlite3
      
      # Connect to the database
      conn = sqlite3.connect(':memory:')  # For demonstration, using an in-memory database
      cursor = conn.cursor()
      
      # Create a table and insert some example data
      cursor.execute('''
      CREATE TABLE people (
          name TEXT,
          age INTEGER
      )
      ''')
      cursor.executemany('''
      INSERT INTO people (name, age) VALUES (?, ?)
      ''', [('John', 20), ('Alice', 30), ('Bob', 40)])
      
      # Query for people with age greater than the specified value
      cursor.execute('''
      SELECT name, age FROM people WHERE age > ?
      ''', (age,))
      
      # Fetch and return the results
      results = cursor.fetchall()
      
      # Close the connection
      conn.close()
      
      return results