title: Check and return Boolean when there is substring in string
body: <p>Hi I am searching only the exact substring from string column and return True/False.</p>
  <p><a href="https://i.stack.imgur.com/xuln0.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/xuln0.png" alt="enter image description here" /></a></p>
  <p>Row-3,4,5 has sting 'abc' (case-sensitive) but when i tried to return it returns TRUE for all rows<br />
  Below is code i have tried.</p>
  <pre><code>df['try_output'] = df['String1'].str.contains('ABC',case = False)
  </code></pre>
  <p>Is there any modification in above statement to get output column '<strong>Required_Output</strong>'</p>