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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 string_to_identity(identity_str):
 """Parse string into Identity dictionary."""

    m = _identity_regexp.match(identity_str)
    result = m.groupdict()
    log.debug('parsed identity: %s', result)
    return {k: v for k, v in result.items() if v}