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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 find_project_dir(path=os.getcwd()):
 """Attempt to find the project root, returns None if not found"""

    path_split = os.path.split(path)
    while path_split[1]:
        if in_armstrong_project(path):
            return path
        path = path_split[0]
        path_split = os.path.split(path)
    # we ran out of parents
    return None