title: AttributeError: 'str' object has no attribute 'execute'
body: <p><strong>I want to add an option but where do I have a mistake?</strong> </p>
  
  <pre><code>conn=sqlite3.connect('tutorial.db')
  c=conn.cursor()
  
  def create_table():
    c.execute('CREATE TABLE IF NOT EXISTS test (UNIX REAL, datestamp TEXT, keyword TEXT, value REAL)')
  
  def data_entry(a,b,c,d):
    c.execute("INSERT INTO test VALUES ({}, '{}', '{}', {})".format(a,b,c,d))
    conn.commit()
    c.close()
    conn.close()
  #create_table()
  data_entry(1,"test","test2",3)
  </code></pre>