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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 _regexSearchKeyValueCombo(policy_data, policy_regpath, policy_regkey):
    '''
    helper function to do a search of Policy data from a registry.pol file
    for a policy_regpath and policy_regkey combo
    '''
    if policy_data:
        specialValueRegex = salt.utils.stringutils.to_bytes(r'(\*\*Del\.|\*\*DelVals\.){0,1}')
        _thisSearch = b''.join([salt.utils.stringutils.to_bytes(r'\['),
                               re.escape(policy_regpath),
                               b'\00;',
                               specialValueRegex,
                               re.escape(policy_regkey),
                               b'\00;'])
        match = re.search(_thisSearch, policy_data, re.IGNORECASE)
        if match:
            # add 2 so we get the ']' and the \00
            # to return the full policy entry
            return policy_data[match.start():(policy_data.index(b']', match.end())) + 2]

    return None