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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 create_securityhash(action_tuples):
 """ Create a SHA1 hash based on the KEY and action string """

    from settings import SECRET_KEY

    action_string = "".join(["_%s%s" % a for a in action_tuples])
    security_hash = sha1(action_string + SECRET_KEY).hexdigest()
    return security_hash