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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 valid_path(value):
    "Validate a cookie path ASCII string"
    # Generate UnicodeDecodeError if path can't store as ASCII.
    value.encode("ascii")
    # Cookies without leading slash will likely be ignored, raise ASAP.
    if not (value and value[0] == "/"):
        return False
    if not Definitions.PATH_RE.match(value):
        return False
    return True