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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 Validate(self, sections=None, parameters=None):
 """Validate sections or individual parameters. The GRR configuration file contains several sections, used by different components. Many of these components don't care about other sections. This method allows a component to declare in advance what sections and parameters it cares about, and have these validated. Args: sections: A list of sections to validate. All parameters within the section are validated. parameters: A list of specific parameters (in the format section.name) to validate. Returns: dict of {parameter: Exception}, where parameter is a section.name string. """

    if isinstance(sections, string_types):
      sections = [sections]

    if sections is None:
      sections = []

    if parameters is None:
      parameters = []

    validation_errors = {}
    for section in sections:
      for descriptor in self.type_infos:
        if descriptor.name.startswith(section + "."):
          try:
            self.Get(descriptor.name)
          except (Error, ValueError) as e:
            validation_errors[descriptor.name] = e

    for parameter in parameters:
      for descriptor in self.type_infos:
        if parameter == descriptor.name:
          try:
            self.Get(descriptor.name)
          except (Error, ValueError) as e:
            validation_errors[descriptor.name] = e

    return validation_errors