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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 _create_conversion_trie(strict):
 """ Create the trie for betacode conversion. Args: text: The beta code text to convert. All of this text must be betacode. strict: Flag to allow for flexible diacritic order on input. Returns: The trie for conversion. """

    t = pygtrie.CharTrie()

    for beta, uni in _map.BETACODE_MAP.items():
        if strict:
            t[beta] = uni
        else:
            # The order of accents is very strict and weak. Allow for many orders of
            # accents between asterisk and letter or after letter. This does not
            # introduce ambiguity since each betacode token only has one letter and
            # either starts with a asterisk or a letter.
            diacritics = beta[1:]

            perms = itertools.permutations(diacritics)
            for perm in perms:
                perm_str = beta[0] + ''.join(perm)
                t[perm_str.lower()] = uni
                t[perm_str.upper()] = uni

    return t