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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_source_and_pgp_key(source_and_key):
 """Look for a pgp key ID or ascii-armor key in the given input. :param source_and_key: Sting, "source_spec|keyid" where '|keyid' is optional. :returns (source_spec, key_id OR None) as a tuple. Returns None for key_id if there was no '|' in the source_and_key string. """

    try:
        source, key = source_and_key.split('|', 2)
        return source, key or None
    except ValueError:
        return source_and_key, None