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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():
 """Runs up the stack to find the location of manage.py which will be considered a project base path. :rtype: str|unicode """

    frame = inspect.currentframe()

    while True:
        frame = frame.f_back
        fname = frame.f_globals['__file__']

        if os.path.basename(fname) == 'manage.py':
            break

    return os.path.dirname(fname)