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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 get_datasource(name, orgname=None, profile='grafana'):
    '''
    Show a single datasource in an organisation.

    name
        Name of the datasource.

    orgname
        Name of the organization.

    profile
        Configuration profile used to connect to the Grafana instance.
        Default is 'grafana'.

    CLI Example:

    .. code-block:: bash

        salt '*' grafana4.get_datasource <name> <orgname>
    '''
    data = get_datasources(orgname=orgname, profile=profile)
    for datasource in data:
        if datasource['name'] == name:
            return datasource
    return None