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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 hacking_no_cr(physical_line):
 r"""Check that we only use newlines not carriage returns. Okay: import os\nimport sys # pep8 doesn't yet replace \r in strings, will work on an # upstream fix H903 import os\r\nimport sys """

    pos = physical_line.find('\r')
    if pos != -1 and pos == (len(physical_line) - 2):
        return (pos, "H903: Windows style line endings not allowed in code")