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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_unit_exist(unit_id):
 """ Return True if the unit 'unid_id' exists. Otherwise return False """

    attribute = 'objectClass'
    response = LDAP_search(
        pattern_search="(uniqueidentifier={})".format(unit_id),
        attribute=attribute
    )
    try:
        unit_exist = 'EPFLorganizationalUnit' in response[0]['attributes'][attribute]
    except Exception:
        return False

    return unit_exist