title: How to check if there exists a row with a certain column value in pandas dataframe
body: <p>Very new to pandas.</p>
  
  <p>Is there a way to check given a pandas dataframe, if there exists a row with a certain column value. Say I have a column 'Name' and I need to check for a certain name if it exists.</p>
  
  <p>And once I do this, I will need to make a similar query, but with a bunch of values at a time.
  I read that there is 'isin', but I'm not sure how to use it. So I need to make a query such that I get all the rows which have 'Name' column matching to any of the values in a big array of names.</p>