'Args:
names(list): list of string, the names of the tensors to monitor
on the progress bar.'

def __init__(self, names=[]):

    super(ProgressBar, self).__init__()
    self._names = [get_op_tensor_name(n)[1] for n in names]
    self._tags = [get_op_tensor_name(n)[0].split('/')[(-1)] for n in names]
    self._bar = None
