title: Equivalent of "whos" command in NumPy
body: <p>I am new to Numpy and trying to search for a function to list out the variables along with their sizes (both the matrix dimensions as well as memory usage). </p>
  
  <p>I am essentially looking for an equivalent of the "whos" command in MATLAB and Octave. Does there exist any such command in NumPy?</p>