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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 get_pycons3rt_home_dir():
 """Returns the pycons3rt home directory based on OS :return: (str) Full path to pycons3rt home :raises: OSError """

    if platform.system() == 'Linux':
        return os.path.join(os.path.sep, 'etc', 'pycons3rt')
    elif platform.system() == 'Windows':
        return os.path.join('C:', os.path.sep, 'pycons3rt')
    elif platform.system() == 'Darwin':
        return os.path.join(os.path.expanduser('~'), '.pycons3rt')
    else:
        raise OSError('Unsupported Operating System')