import os

# Use this to manage 'cd' context
from contextlib import contextmanager


@contextmanager
def cd(newdir):
    """
    Return to prevdir when context is exited.
    Use in the following manner:

       with cd("foodir"):
          operation1_in_foodir
          operation2_in_foodir

       operation3_in_prevdir
    """
    prevdir = os.getcwd()
    os.chdir(os.path.expanduser(newdir))
    try:
        yield
    finally:
        os.chdir(prevdir)