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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_content_length(environ):
 """Returns the content length from the WSGI environment as integer. If it's not available `None` is returned. .. versionadded:: 0.9 :param environ: the WSGI environ to fetch the content length from. """

    content_length = environ.get('CONTENT_LENGTH')
    if content_length is not None:
        try:
            return max(0, int(content_length))
        except (ValueError, TypeError):
            pass