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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_trailing_whitespace(marker, s):
 """Return the whitespace content trailing the given 'marker' in string 's', up to and including a newline. """

    suffix = ''
    start = s.index(marker) + len(marker)
    i = start
    while i < len(s):
        if s[i] in ' \t':
            suffix += s[i]
        elif s[i] in '\r\n':
            suffix += s[i]
            if s[i] == '\r' and i + 1 < len(s) and s[i + 1] == '\n':
                suffix += s[i + 1]
            break
        else:
            break
        i += 1
    return suffix