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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 account_policy(name=None, allow_users_to_change_password=None,
                   hard_expiry=None, max_password_age=None,
                   minimum_password_length=None, password_reuse_prevention=None,
                   require_lowercase_characters=None, require_numbers=None,
                   require_symbols=None, require_uppercase_characters=None,
                   region=None, key=None, keyid=None, profile=None):
    '''
    Change account policy.

    .. versionadded:: 2015.8.0

    name (string)
        The name of the account policy

    allow_users_to_change_password (bool)
        Allows all IAM users in your account to
        use the AWS Management Console to change their own passwords.

    hard_expiry (bool)
        Prevents IAM users from setting a new password after their
        password has expired.

    max_password_age (int)
        The number of days that an IAM user password is valid.

    minimum_password_length (int)
        The minimum number of characters allowed in an IAM user password.

    password_reuse_prevention (int)
        Specifies the number of previous passwords
        that IAM users are prevented from reusing.

    require_lowercase_characters (bool)
        Specifies whether IAM user passwords
        must contain at least one lowercase character from the ISO basic Latin alphabet (a to z).

    require_numbers (bool)
        Specifies whether IAM user passwords must contain at
        least one numeric character (0 to 9).

    require_symbols (bool)
        Specifies whether IAM user passwords must contain at
        least one of the following non-alphanumeric characters: ! @ # $ % ^ & * ( ) _ + - = [ ] { } | '

    require_uppercase_characters (bool)
        Specifies whether IAM user passwords must
        contain at least one uppercase character from the ISO basic Latin alphabet (A to Z).

    region (string)
        Region to connect to.

    key (string)
        Secret key to be used.

    keyid (string)
        Access key to be used.

    profile (dict)
        A dict with region, key and keyid, or a pillar key (string)
    '''
    config = locals()
    ret = {'name': 'Account Policy', 'result': True, 'comment': '', 'changes': {}}
    info = __salt__['boto_iam.get_account_policy'](region, key, keyid, profile)
    if not info:
        ret['comment'] = 'Account policy is not Enabled.'
        ret['result'] = False
        return ret
    for key, value in config.items():
        if key in ('region', 'key', 'keyid', 'profile', 'name'):
            continue
        if value is not None and six.text_type(info[key]) != six.text_type(value).lower():
            ret['comment'] = ' '.join([ret['comment'], 'Policy value {0} has been set to {1}.'.format(value, info[key])])
            ret['changes'][key] = six.text_type(value).lower()
    if not ret['changes']:
        ret['comment'] = 'Account policy is not changed.'
        return ret
    if __opts__['test']:
        ret['comment'] = 'Account policy is set to be changed.'
        ret['result'] = None
        return ret
    if __salt__['boto_iam.update_account_password_policy'](allow_users_to_change_password,
                                                           hard_expiry,
                                                           max_password_age,
                                                           minimum_password_length,
                                                           password_reuse_prevention,
                                                           require_lowercase_characters,
                                                           require_numbers,
                                                           require_symbols,
                                                           require_uppercase_characters,
                                                           region, key, keyid, profile):
        return ret
    ret['comment'] = 'Account policy is not changed.'
    ret['changes'] = {}
    ret['result'] = False
    return ret