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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 _trim_base64(s):
 """Trim and hash base64 strings"""

    if len(s) > 64 and _base64.match(s.replace('\n', '')):
        h = hash_string(s)
        s = '%s...<snip base64, md5=%s...>' % (s[:8], h[:16])
    return s