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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def initialize_experiment_package(path):
 """Make the specified directory importable as the `dallinger_experiment` package."""

    # Create __init__.py if it doesn't exist (needed for Python 2)
    init_py = os.path.join(path, "__init__.py")
    if not os.path.exists(init_py):
        open(init_py, "a").close()

    # Retain already set experiment module
    if sys.modules.get("dallinger_experiment") is not None:
        return
    dirname = os.path.dirname(path)
    basename = os.path.basename(path)
    sys.path.insert(0, dirname)
    package = __import__(basename)
    if path not in package.__path__:
        raise Exception("Package was not imported from the requested path!")
    sys.modules["dallinger_experiment"] = package
    package.__package__ = "dallinger_experiment"
    sys.path.pop(0)