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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 path_exists(source, path, separator='/'):
 """Check a dict for the existence of a value given a path to it. :param source: a dict to read data from :param path: a key or path to a key (path is delimited by `separator`) :keyword separator: the separator used in the path (ex. Could be "." for a json/mongodb type of value) """

    if path == separator and isinstance(source, dict):
        return True
    parts = path.strip(separator).split(separator)
    if not parts:
        return False
    current = source
    for part in parts:
        if not isinstance(current, dict):
            return False
        if part not in current:
            return False
        current = current[part]
    return True