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# scipy.constants.value

`scipy.constants.``value`(key)

  Value in physical_constants indexed by key

  Parameters: | key : Python string or unicode Key in dictionary `physical_constants`
  Returns: | value : float Value in `physical_constants` corresponding to key

  See also

  `codata`
    Contains the description of `physical_constants`, which, as a dictionary literal object, does not itself possess a docstring.

  Examples

      >>> from scipy import constants
      >>> constants.value(u'elementary charge')
          1.6021766208e-19