code: def get_pv(self, device):
          
          if not os.path.exists(device):
              raise ValueError("%s does not exist." % device)
          return PhysicalVolume(self, name=device)
docs: Returns the physical volume associated with the given device::
  
              from lvm2py import *
  
              lvm = LVM()
              vg = lvm.get_vg("myvg", "w")
              vg.get_pv("/dev/sdb1")
  
          *Args:*
  
          *       device (str):   An existing device.
  
          *Raises:*
  
          *       ValueError, HandleError