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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 trailing_whitespace(physical_line):
 r"""Trailing whitespace is superfluous. The warning returned varies on whether the line itself is blank, for easier filtering for those who want to indent their blank lines. Okay: spam(1)\n# W291: spam(1) \n# W293: class Foo(object):
\n \n bang = 12 """

    physical_line = physical_line.rstrip('\n')    # chr(10), newline
    physical_line = physical_line.rstrip('\r')    # chr(13), carriage return
    physical_line = physical_line.rstrip('\x0c')  # chr(12), form feed, ^L
    stripped = physical_line.rstrip(' \t\v')
    if physical_line != stripped:
        if stripped:
            return len(stripped), "W291 trailing whitespace"
        else:
            return 0, "W293 blank line contains whitespace"