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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 validate(path, regex=None):
 """ Validate that all the keys in the given list of path components are valid, given that they do not contain the separator, and match any optional regex given. """

    validated = []
    for elem in path:
        key = elem[0]
        strkey = str(key)
        if (regex and (not regex.findall(strkey))):
            raise dpath.exceptions.InvalidKeyName("{} at {} does not match the expression {}"
                                                  "".format(strkey,
                                                            validated,
                                                            regex.pattern))
        validated.append(strkey)