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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 is_file(jottapath, JFS):
 """Check if a file exists on jottacloud"""

    log.debug("is_file %r", jottapath)
    try:
        jf = JFS.getObject(jottapath)
    except JFSNotFoundError:
        return False
    return isinstance(jf, JFSFile)