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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 which(self, fname):
 """Returns the fully qualified path by searching Path of the given name"""

        for pe in os.environ['PATH'].split(os.pathsep):
            checkname = os.path.join(pe, fname)
            if os.access(checkname, os.X_OK) and not os.path.isdir(checkname):
                return checkname
        return None