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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_key_id_from_key(self, key):
 """ _get_key_id_from_key returns the key id from a key, if found. otherwise it just returns the key to be used as the key id. Keyword arguments: key -- The key to derive the ID from. If curly braces are found in the key, then the contents of the curly braces are used as the key id for the key. Returns the key id portion of the key, or the whole key if no hash tags are present. """

        key_id = key

        regex = '{0}([^{1}]*){2}'.format(self._hash_start, self._hash_stop,
                                         self._hash_stop)
        m = re.search(regex, key)
        if m is not None:
            # Use what's inside the hash tags as the key id, if present.
            # Otherwise the whole key will be used as the key id.
            key_id = m.group(1)

        return key_id