docs: def get_polygon_from_postgis(conn, schema, table, gcol='geom', union=False):
      r"""A one-line summary that does not use variable names or the
      function name.
  
      Several sentences providing an extended description. Refer to
      variables using back-ticks, e.g. `var`.
  
      Parameters
      ----------
      var1 : array_like
          Array_like means all those objects -- lists, nested lists, etc. --
          that can be converted to an array.  We can also refer to
          variables like `var1`.
      var2 : int
          The type above can either refer to an actual Python type
          (e.g. ``int``), or describe the type of the variable in more
          detail, e.g. ``(N,) ndarray`` or ``array_like``.
      Long_variable_name : {'hi', 'ho'}, optional
          Choices in brackets, default first when optional.
  
      Returns
      -------
      type
          Explanation of anonymous return value of type ``type``.
      describe : type
          Explanation of return value named `describe`.
      out : type
          Explanation of `out`.
  
      Other Parameters
      ----------------
      only_seldom_used_keywords : type
          Explanation
      common_parameters_listed_above : type
          Explanation
  
      Raises
      ------
      BadException
          Because you shouldn't have done that.
  
      See Also
      --------
      otherfunc : relationship (optional)
      newfunc : Relationship (optional), which could be fairly long, in which
                case the line wraps here.
      thirdfunc, fourthfunc, fifthfunc
  
      Notes
      -----
      Notes about the implementation algorithm (if needed).
  
      This can have multiple paragraphs.
  
      You may include some math:
  
      .. math:: X(e^{j\omega } ) = x(n)e^{ - j\omega n}
  
      And even use a greek symbol like :math:`omega` inline.
  
      References
      ----------
      Cite the relevant literature, e.g. [1]_.  You may also cite these
      references in the notes section above.
  
      .. [1] O. McNoleg, "The integration of GIS, remote sensing,
         expert systems and adaptive co-kriging for environmental habitat
         modelling of the Highland Haggis using object-oriented, fuzzy-logic
         and neural-network techniques," Computers & Geosciences, vol. 22,
         pp. 585-588, 1996.
  
      Examples
      --------
      These are written in doctest format, and should illustrate how to
      use the function.
  
      >>> a=[1,2,3]
      >>> print [x + 3 for x in a]
      [4, 5, 6]
      >>> print "a\n\nb"
      a
      b
  
      """
      # TODO@Günni
      logging.debug('Getting polygon from DB table')
      if union:
          geo_string = 'st_union({0})'.format(gcol)
      else:
          geo_string = '{0}'.format(gcol)
  
      sql = '''
          SELECT st_astext(ST_Transform({geo_string}, 4326))
          FROM {schema}.{table};
      '''.format(**{'geo_string': geo_string, 'schema': schema, 'table': table})
      return wkt_loads(conn.execute(sql).fetchone()[0])