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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_mapping_variable(variable_name, variables_mapping):
 """ get variable from variables_mapping. Args: variable_name (str):
 variable name variables_mapping (dict):
 variables mapping Returns: mapping variable value. Raises: exceptions.VariableNotFound: variable is not found. """

    try:
        return variables_mapping[variable_name]
    except KeyError:
        raise exceptions.VariableNotFound("{} is not found.".format(variable_name))