title: changing row values of pandas from dictionary
body: <p>I have a dataframe where i need to change row values if it is present in a dictionary like this:</p>
  
  <pre><code>dict = {"A":Apple:"B":Ball,"C":Cat}
  
          c1          c2      c3
  0       A          Tree     GH
  1       B          Train    GC
  2       C          Yarn     GR
  </code></pre>
  
  <p>I want the column c1 values to be changed from the dict if it is present. </p>